From dd836979c38dc3a5793c423b68a8e1f1f26eef7c Mon Sep 17 00:00:00 2001
From: thomasdenecker <thomas.denecker@gmail.com>
Date: Tue, 22 Aug 2023 18:17:28 +0200
Subject: [PATCH] feat: impove tool display

---
 components/GithubBtn.vue    |    2 +-
 components/content/Awk.vue  |  128 +
 components/content/Grep.vue |   21 +-
 components/content/Sed.vue  |   11 +-
 public/man/gawk.html        | 4882 +++++++++++++++++++++++++++++++++++
 5 files changed, 5033 insertions(+), 11 deletions(-)
 create mode 100644 components/content/Awk.vue
 create mode 100644 public/man/gawk.html

diff --git a/components/GithubBtn.vue b/components/GithubBtn.vue
index 9c185dc..1418b6b 100644
--- a/components/GithubBtn.vue
+++ b/components/GithubBtn.vue
@@ -11,7 +11,7 @@
         style="background-color: transparent !important"
       >
         <p class="ma-0">{{ config.public.repo_name }}</p>
-        <p class="text-caption ma-0">
+        <p class="text-caption ma-0" v-if="ghRelease">
           <v-icon>mdi-tag-outline</v-icon> {{ ghRelease.tag_name }}
           <v-icon>mdi-star-outline</v-icon> {{ ghValue.stargazers_count }}
           <v-icon>mdi-source-fork</v-icon> {{ ghValue.forks_count }}
diff --git a/components/content/Awk.vue b/components/content/Awk.vue
new file mode 100644
index 0000000..e6bd096
--- /dev/null
+++ b/components/content/Awk.vue
@@ -0,0 +1,128 @@
+<template>
+    <p class="text-h6">File content</p>
+    <p>
+      <b
+        ><v-icon>mdi-information</v-icon> This content will be written to the file
+        <code>data.txt</code></b
+      >
+    </p>
+    <div style="max-height: 200px; overflow-y: auto">
+      <div :id="idEditor" style="width: 100%; height: 200px">
+        {{ text }}
+      </div>
+    </div>
+  
+    <p class="text-h6">Command</p>
+    <p>
+      <b
+        ><v-icon>mdi-information</v-icon> The file name must always be
+        <code>data.txt</code></b
+      >
+    </p>
+    <v-dialog v-model="dialog" width="75%">
+      <template v-slot:activator="{ props }">
+        <v-btn color="primary" v-bind="props" size="small" class="mb-4">
+          <v-icon>mdi-book</v-icon> Read man
+        </v-btn>
+      </template>
+  
+      <v-card>
+        <v-card-text style="height: 90vh">
+          <iframe
+            src="/man/gawk.html"
+            frameborder="0"
+            style="height: 100%; width: 100%"
+          ></iframe>
+        </v-card-text>
+      </v-card>
+    </v-dialog>
+  
+    <v-text-field
+      v-model="commandInput"
+      style="font-family: monospace, monospace !important"
+    ></v-text-field>
+    <v-btn class="mt-4" @click="runTool">Run tool </v-btn>
+    <p class="text-h6">Output</p>
+    <pre :id="idOutput">Await run click...</pre>
+    <v-card color="info">
+      <v-card-text v-if="noResult">
+        <v-icon>mdi-information</v-icon> No result
+      </v-card-text>
+    </v-card>
+  </template>
+      
+    <script>
+  import Aioli from "@biowasm/aioli";
+  import ace from "ace-builds";
+  
+  export default {
+    props: {
+      text: String,
+      command: String,
+    },
+    setup(props) {
+      var id = new Date().valueOf();
+      var idEditor = "editorArea" + id;
+      var idOutput = "output" + id;
+  
+      const route = useRoute();
+      let tool = route.params.tool;
+  
+      return { idEditor, idOutput, tool };
+    },
+    data() {
+      return {
+        dialog: false,
+        editor: null,
+        commandInput: null,
+        noResult: false,
+      };
+    },
+    mounted() {
+      this.commandInput = this.command;
+      this.editor = ace.edit(this.idEditor, {
+        tabSize: 4,
+        // readOnly: this.readOnly,
+        autoScrollEditorIntoView: true,
+        maxLines: 50,
+        minLines: 1,
+      });
+    },
+    methods: {
+      async runTool() {
+        document.getElementById(this.idOutput).innerHTML = "Loading...";
+        this.noResult = false;
+  
+        const CLI = await new Aioli(["gawk/5.1.0"]);
+  
+        // Create sample file
+        var dataEditor = {
+          name: "data.txt",
+          data: this.editor.getValue(),
+        };
+        await CLI.mount(dataEditor);
+        console.log(this.commandInput);
+  
+        var temp = this.commandInput;
+        temp = temp.replace(this.tool, "").trim();
+        var params = this.parseFlags(temp)
+          //.map((d) => d.replaceAll('"', ""))
+          .map((d) => d.replaceAll("'", ""));
+        console.log(params);
+        const output = await CLI.exec("gawk", params);
+        if (output == "") {
+          this.noResult = true;
+        }
+        console.log(output);
+        document.getElementById(this.idOutput).innerHTML = output;
+      },
+      parseFlags(flags) {
+        // Source: https://stackoverflow.com/a/16261693
+        return flags.match(/(?:[^\s']+|'[^']*')+/g) || [];
+      },
+    },
+  };
+  </script>
+      
+      <style>
+  </style>
\ No newline at end of file
diff --git a/components/content/Grep.vue b/components/content/Grep.vue
index f46b0cf..cec53ee 100644
--- a/components/content/Grep.vue
+++ b/components/content/Grep.vue
@@ -1,7 +1,10 @@
 <template>
   <p class="text-h6">File content</p>
   <p>
-    <b><v-icon>mdi-information</v-icon> This content will be written to the file <code>data.txt</code></b>
+    <b
+      ><v-icon>mdi-information</v-icon> This content will be written to the file
+      <code>data.txt</code></b
+    >
   </p>
   <div style="max-height: 200px; overflow-y: auto">
     <div :id="idEditor" style="width: 100%; height: 200px">
@@ -11,7 +14,15 @@
 
   <p class="text-h6">Command</p>
   <p>
-    <b><v-icon>mdi-information</v-icon> The file name must always be <code>data.txt</code></b>
+    <b
+      ><v-icon>mdi-information</v-icon> The file name must always be
+      <code>data.txt</code></b
+    >
+  </p>
+  <p>
+    <b
+      ><v-icon>mdi-information</v-icon> Use simple quote for write a text argument.</b
+    >
   </p>
   <v-dialog v-model="dialog" width="75%">
     <template v-slot:activator="{ props }">
@@ -99,9 +110,7 @@ export default {
 
       var temp = this.commandInput;
       temp = temp.replace(this.tool, "").trim();
-      var params = this.parseFlags(temp)
-        .map((d) => d.replaceAll('"', ""))
-        .map((d) => d.replaceAll("'", ""));
+      var params = this.parseFlags(temp).map((d) => d.replaceAll("'", ""));
       console.log(params);
       const output = await CLI.exec("grep", params);
       if (output == "") {
@@ -112,7 +121,7 @@ export default {
     },
     parseFlags(flags) {
       // Source: https://stackoverflow.com/a/16261693
-      return flags.match(/(?:[^\s"]+|"[^"]*")+/g) || [];
+      return flags.match(/(?:[^\s']+|'[^']*')+/g) || [];
     },
   },
 };
diff --git a/components/content/Sed.vue b/components/content/Sed.vue
index 2eb97fe..6f7809f 100644
--- a/components/content/Sed.vue
+++ b/components/content/Sed.vue
@@ -19,6 +19,11 @@
       <code>data.txt</code></b
     >
   </p>
+  <p>
+    <b
+      ><v-icon>mdi-information</v-icon> Use simple quote for write a text argument.</b
+    >
+  </p>
   <v-dialog v-model="dialog" width="75%">
     <template v-slot:activator="{ props }">
       <v-btn color="primary" v-bind="props" size="small" class="mb-4">
@@ -112,9 +117,7 @@ export default {
 
       var temp = this.commandInput;
       temp = temp.replace(this.tool, "").trim();
-      var params = this.parseFlags(temp)
-        .map((d) => d.replaceAll('"', ""))
-        .map((d) => d.replaceAll("'", ""));
+      var params = this.parseFlags(temp).map((d) => d.replaceAll("'", ""));
       console.log(params);
       const output = await CLI.exec("sed", params);
       if (output == "") {
@@ -125,7 +128,7 @@ export default {
     },
     parseFlags(flags) {
       // Source: https://stackoverflow.com/a/16261693
-      return flags.match(/(?:[^\s"]+|"[^"]*")+/g) || [];
+      return flags.match(/(?:[^\s']+|'[^']*')+/g) || [];
     },
   },
 };
diff --git a/public/man/gawk.html b/public/man/gawk.html
new file mode 100644
index 0000000..8a00612
--- /dev/null
+++ b/public/man/gawk.html
@@ -0,0 +1,4882 @@
+<!-- Creator     : groff version 1.22.2 -->
+<!-- CreationDate: Tue Aug 22 17:22:57 2023 -->
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
+"http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta name="generator" content="groff -Thtml, see www.gnu.org">
+<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta name="Content-Style" content="text/css">
+<style type="text/css">
+       p       { margin-top: 0; margin-bottom: 0; vertical-align: top }
+       pre     { margin-top: 0; margin-bottom: 0; vertical-align: top }
+       table   { margin-top: 0; margin-bottom: 0; vertical-align: top }
+       h1      { text-align: center }
+</style>
+<title>GAWK</title>
+
+</head>
+<body>
+
+<h1 align="center">GAWK</h1>
+
+<a href="#NAME">NAME</a><br>
+<a href="#SYNOPSIS">SYNOPSIS</a><br>
+<a href="#DESCRIPTION">DESCRIPTION</a><br>
+<a href="#OPTION FORMAT">OPTION FORMAT</a><br>
+<a href="#OPTIONS">OPTIONS</a><br>
+<a href="#AWK PROGRAM EXECUTION">AWK PROGRAM EXECUTION</a><br>
+<a href="#VARIABLES, RECORDS AND FIELDS">VARIABLES, RECORDS AND FIELDS</a><br>
+<a href="#PATTERNS AND ACTIONS">PATTERNS AND ACTIONS</a><br>
+<a href="#USER-DEFINED FUNCTIONS">USER-DEFINED FUNCTIONS</a><br>
+<a href="#DYNAMICALLY LOADING NEW FUNCTIONS">DYNAMICALLY LOADING NEW FUNCTIONS</a><br>
+<a href="#SIGNALS">SIGNALS</a><br>
+<a href="#INTERNATIONALIZATION">INTERNATIONALIZATION</a><br>
+<a href="#POSIX COMPATIBILITY">POSIX COMPATIBILITY</a><br>
+<a href="#HISTORICAL FEATURES">HISTORICAL FEATURES</a><br>
+<a href="#GNU EXTENSIONS">GNU EXTENSIONS</a><br>
+<a href="#ENVIRONMENT VARIABLES">ENVIRONMENT VARIABLES</a><br>
+<a href="#EXIT STATUS">EXIT STATUS</a><br>
+<a href="#VERSION INFORMATION">VERSION INFORMATION</a><br>
+<a href="#AUTHORS">AUTHORS</a><br>
+<a href="#BUG REPORTS">BUG REPORTS</a><br>
+<a href="#BUGS">BUGS</a><br>
+<a href="#SEE ALSO">SEE ALSO</a><br>
+<a href="#EXAMPLES">EXAMPLES</a><br>
+<a href="#ACKNOWLEDGEMENTS">ACKNOWLEDGEMENTS</a><br>
+<a href="#COPYING PERMISSIONS">COPYING PERMISSIONS</a><br>
+
+<hr>
+
+
+<h2>NAME
+<a name="NAME"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">gawk &minus;
+pattern scanning and processing language</p>
+
+<h2>SYNOPSIS
+<a name="SYNOPSIS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><b>gawk</b> [
+<small>POSIX</small> or <small>GNU</small> style options ]
+<b>&minus;f</b> <i>program-file</i> [ <b>&minus;&minus;</b>
+] file ... <b><br>
+gawk</b> [ <small>POSIX</small> or <small>GNU</small> style
+options ] [ <b>&minus;&minus;</b> ] <i>program-text</i> file
+...</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>pgawk</b> [
+<small>POSIX</small> or <small>GNU</small> style options ]
+<b>&minus;f</b> <i>program-file</i> [ <b>&minus;&minus;</b>
+] file ... <b><br>
+pgawk</b> [ <small>POSIX</small> or <small>GNU</small> style
+options ] [ <b>&minus;&minus;</b> ] <i>program-text</i> file
+...</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>dgawk</b> [
+<small>POSIX</small> or <small>GNU</small> style options ]
+<b>&minus;f</b> <i>program-file</i> [ <b>&minus;&minus;</b>
+] file ...</p>
+
+<h2>DESCRIPTION
+<a name="DESCRIPTION"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i> is
+the <small>GNU</small> Project&rsquo;s implementation of the
+<small>AWK</small> programming language. It conforms to the
+definition of the language in the <small>POSIX</small>
+1003.1 Standard. This version in turn is based on the
+description in <i>The AWK Programming Language</i>, by Aho,
+Kernighan, and Weinberger. <i>Gawk</i> provides the
+additional features found in the current version of
+<small>UNIX</small> <i>awk</i> and a number of
+<small>GNU</small> -specific extensions.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The command
+line consists of options to <i>gawk</i> itself, the
+<small>AWK</small> program text (if not supplied via the
+<b>&minus;f</b> or <b>&minus;&minus;file</b> options), and
+values to be made available in the <b>ARGC</b> and
+<b>ARGV</b> pre-defined <small>AWK</small> variables.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Pgawk</i> is
+the profiling version of <i>gawk</i>. It is identical in
+every way to <i>gawk</i>, except that programs run more
+slowly, and it automatically produces an execution profile
+in the file <b>awkprof.out</b> when done. See the
+<b>&minus;&minus;profile</b> option, below.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Dgawk</i> is
+an <i>awk</i> debugger. Instead of running the program
+directly, it loads the AWK source code and then prompts for
+debugging commands. Unlike <i>gawk</i> and <i>pgawk</i>,
+<i>dgawk</i> only processes AWK program source provided with
+the <b>&minus;f</b> option. The debugger is documented in
+<i>GAWK: Effective AWK Programming</i>.</p>
+
+<h2>OPTION FORMAT
+<a name="OPTION FORMAT"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>
+options may be either traditional <small>POSIX</small>
+-style one letter options, or <small>GNU</small> -style long
+options. <small>POSIX</small> options start with a single
+&ldquo;&minus;&rdquo;, while long options start with
+&ldquo;&minus;&minus;&rdquo;. Long options are provided for
+both <small>GNU</small> -specific features and for
+<small>POSIX</small> -mandated features.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>-
+specific options are typically used in long-option form.
+Arguments to long options are either joined with the option
+by an <b>=</b> sign, with no intervening spaces, or they may
+be provided in the next command line argument. Long options
+may be abbreviated, as long as the abbreviation remains
+unique.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Additionally,
+each long option has a corresponding short option, so that
+the option&rsquo;s functionality may be used from within
+<b>#!</b> executable scripts.</p>
+
+<h2>OPTIONS
+<a name="OPTIONS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>
+accepts the following options. Standard options are listed
+first, followed by options for <i>gawk</i> extensions,
+listed alphabetically by short option. <b><br>
+&minus;f</b> <i>program-file</i> <b><br>
+&minus;&minus;file</b> <i>program-file</i></p>
+
+<p style="margin-left:22%;">Read the <small>AWK</small>
+program source from the file <i>program-file</i>, instead of
+from the first command line argument. Multiple
+<b>&minus;f</b> (or <b>&minus;&minus;file</b>) options may
+be used.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="7%">
+
+
+<p><b>&minus;F</b> <i>fs</i></p></td>
+<td width="82%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;field-separator</b>
+<i>fs</i></p>
+
+<p style="margin-left:22%;">Use <i>fs</i> for the input
+field separator (the value of the <b>FS</b> predefined
+variable).</p>
+
+<p style="margin-left:11%;"><b>&minus;v</b>
+<i>var</i><b>=</b><i>val</i> <b><br>
+&minus;&minus;assign</b> <i>var</i><b>=</b><i>val</i></p>
+
+<p style="margin-left:22%;">Assign the value <i>val</i> to
+the variable <i>var</i>, before execution of the program
+begins. Such variable values are available to the
+<b>BEGIN</b> block of an <small>AWK</small> program.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;b</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;characters&minus;as&minus;bytes</b></p>
+
+<p style="margin-left:22%;">Treat all input data as
+single-byte characters. In other words, don&rsquo;t pay any
+attention to the locale information when attempting to
+process strings as multibyte characters. The
+<b>&minus;&minus;posix</b> option overrides this one.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;c</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;traditional</b></p>
+
+<p style="margin-left:22%;">Run in <i>compatibility</i>
+mode. In compatibility mode, <i>gawk</i> behaves identically
+to <small>UNIX</small> <i>awk</i>; none of the
+<small>GNU</small> -specific extensions are recognized. See
+<b>GNU EXTENSIONS</b>, below, for more information.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;C</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;copyright</b></p>
+
+<p style="margin-left:22%;">Print the short version of the
+<small>GNU</small> copyright information message on the
+standard output and exit successfully.</p>
+
+<p style="margin-left:11%;"><b>&minus;d</b>[<i>file</i>]
+<b><br>
+&minus;&minus;dump-variables</b>[<b>=</b><i>file</i>]</p>
+
+<p style="margin-left:22%;">Print a sorted list of global
+variables, their types and final values to <i>file</i>. If
+no <i>file</i> is provided, <i>gawk</i> uses a file named
+<b>awkvars.out</b> in the current directory. <br>
+Having a list of all the global variables is a good way to
+look for typographical errors in your programs. You would
+also use this option if you have a large program with a lot
+of functions, and you want to be sure that your functions
+don&rsquo;t inadvertently use global variables that you
+meant to be local. (This is a particularly easy mistake to
+make with simple variable names like <b>i</b>, <b>j</b>, and
+so on.)</p>
+
+<p style="margin-left:11%;"><b>&minus;e</b>
+<i>program-text</i> <b><br>
+&minus;&minus;source</b> <i>program-text</i></p>
+
+<p style="margin-left:22%;">Use <i>program-text</i> as
+<small>AWK</small> program source code. This option allows
+the easy intermixing of library functions (used via the
+<b>&minus;f</b> and <b>&minus;&minus;file</b> options) with
+source code entered on the command line. It is intended
+primarily for medium to large <small>AWK</small> programs
+used in shell scripts.</p>
+
+<p style="margin-left:11%;"><b>&minus;E</b> <i>file</i>
+<b><br>
+&minus;&minus;exec</b> <i>file</i></p>
+
+<p style="margin-left:22%;">Similar to <b>&minus;f</b>,
+however, this is option is the last one processed. This
+should be used with <b>#!</b> scripts, particularly for CGI
+applications, to avoid passing in options or source code (!)
+on the command line from a URL. This option disables
+command-line variable assignments.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;g</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;gen&minus;pot</b></p>
+
+<p style="margin-left:22%;">Scan and parse the
+<small>AWK</small> program, and generate a
+<small>GNU</small> <b>.pot</b> (Portable Object Template)
+format file on standard output with entries for all
+localizable strings in the program. The program itself is
+not executed. See the <small>GNU</small> <i>gettext</i>
+distribution for more information on <b>.pot</b> files.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>&minus;h</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>&minus;&minus;help</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>Print a relatively short summary of the available
+options on the standard output. (Per the <i>GNU Coding
+Standards</i>, these options cause an immediate, successful
+exit.)</p> </td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>&minus;L</b> [<i>value</i>]
+<b><br>
+&minus;&minus;lint</b>[<b>=</b><i>value</i>]</p>
+
+<p style="margin-left:22%;">Provide warnings about
+constructs that are dubious or non-portable to other
+<small>AWK</small> implementations. With an optional
+argument of <b>fatal</b>, lint warnings become fatal errors.
+This may be drastic, but its use will certainly encourage
+the development of cleaner <small>AWK</small> programs. With
+an optional argument of <b>invalid</b>, only warnings about
+things that are actually invalid are issued. (This is not
+fully implemented yet.)</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;n</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;non&minus;decimal&minus;data</b></p>
+
+<p style="margin-left:22%;">Recognize octal and hexadecimal
+values in input data. <i>Use this option with great
+caution!</i></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;N</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;use&minus;lc&minus;numeric</b></p>
+
+<p style="margin-left:22%;">This forces <i>gawk</i> to use
+the locale&rsquo;s decimal point character when parsing
+input data. Although the POSIX standard requires this
+behavior, and <i>gawk</i> does so when
+<b>&minus;&minus;posix</b> is in effect, the default is to
+follow traditional behavior and use a period as the decimal
+point, even in locales where the period is not the decimal
+point character. This option overrides the default behavior,
+without the full draconian strictness of the
+<b>&minus;&minus;posix</b> option.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;O</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;optimize</b></p>
+
+<p style="margin-left:22%;">Enable optimizations upon the
+internal representation of the program. Currently, this
+includes just simple constant-folding. The <i>gawk</i>
+maintainer hopes to add additional optimizations over
+time.</p>
+
+
+<p style="margin-left:11%;"><b>&minus;p</b>[<i>prof_file</i>]
+<b><br>
+&minus;&minus;profile</b>[<b>=</b><i>prof_file</i>]</p>
+
+<p style="margin-left:22%;">Send profiling data to
+<i>prof_file</i>. The default is <b>awkprof.out</b>. When
+run with <i>gawk</i>, the profile is just a &ldquo;pretty
+printed&rdquo; version of the program. When run with
+<i>pgawk</i>, the profile contains execution counts of each
+statement in the program in the left margin and function
+call counts for each user-defined function.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;P</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>&minus;&minus;posix</b></p>
+
+<p style="margin-left:22%;">This turns on
+<i>compatibility</i> mode, with the following additional
+restrictions:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="75%">
+
+
+<p><b>\x</b> escape sequences are not recognized.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="75%">
+
+
+<p>Only space and tab act as field separators when
+<b>FS</b> is set to a single space, newline does not.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="75%">
+
+
+<p>You cannot continue lines after <b>?</b> and
+<b>:</b>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="75%">
+
+
+<p>The synonym <b>func</b> for the keyword <b>function</b>
+is not recognized.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="75%">
+
+
+<p>The operators <b>**</b> and <b>**=</b> cannot be used in
+place of <b>^</b> and <b>^=</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>&minus;r</b></p></td>
+<td width="2%"></td>
+<td width="75%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;re&minus;interval</b></p>
+
+<p style="margin-left:22%;">Enable the use of <i>interval
+expressions</i> in regular expression matching (see
+<b>Regular Expressions</b>, below). Interval expressions
+were not traditionally available in the <small>AWK</small>
+language. The <small>POSIX</small> standard added them, to
+make <i>awk</i> and <i>egrep</i> consistent with each other.
+They are enabled by default, but this option remains for use
+with <b>&minus;-traditional</b>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;R</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>&minus;&minus;command</b>
+<i>file</i></p>
+
+<p style="margin-left:22%;"><i>Dgawk</i> only. Read stored
+debugger commands from <i>file</i>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;S</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;sandbox</b></p>
+
+<p style="margin-left:22%;">Runs <i>gawk</i> in sandbox
+mode, disabling the <b>system()</b> function, input
+redirection with <b>getline</b>, output redirection with
+<b>print</b> and <b>printf</b>, and loading dynamic
+extensions. Command execution (through pipelines) is also
+disabled. This effectively blocks a script from accessing
+local resources (except for the files specified on the
+command line).</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;t</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;lint&minus;old</b></p>
+
+<p style="margin-left:22%;">Provide warnings about
+constructs that are not portable to the original version of
+Unix <i>awk</i>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;V</b></p></td>
+<td width="86%">
+</td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;version</b></p>
+
+<p style="margin-left:22%;">Print version information for
+this particular copy of <i>gawk</i> on the standard output.
+This is useful mainly for knowing if the current copy of
+<i>gawk</i> on your system is up to date with respect to
+whatever the Free Software Foundation is distributing. This
+is also useful when reporting bugs. (Per the <i>GNU Coding
+Standards</i>, these options cause an immediate, successful
+exit.)</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>&minus;&minus;</b></p></td>
+<td width="8%"></td>
+<td width="78%">
+
+
+<p>Signal the end of options. This is useful to allow
+further arguments to the <small>AWK</small> program itself
+to start with a &ldquo;&minus;&rdquo;. This provides
+consistency with the argument parsing convention used by
+most other <small>POSIX</small> programs.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">In
+compatibility mode, any other options are flagged as
+invalid, but are otherwise ignored. In normal operation, as
+long as program text has been supplied, unknown options are
+passed on to the <small>AWK</small> program in the
+<b>ARGV</b> array for processing. This is particularly
+useful for running <small>AWK</small> programs via the
+&ldquo;#!&rdquo; executable interpreter mechanism.</p>
+
+<h2>AWK PROGRAM EXECUTION
+<a name="AWK PROGRAM EXECUTION"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">An
+<small>AWK</small> program consists of a sequence of
+pattern-action statements and optional function
+definitions.</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>@include
+&quot;</b><i>filename</i><b>&quot;</b> <i>pattern</i>
+<b>{</b> <i>action statements</i> <b>} <br>
+function</b> <i>name</i><b>(</b><i>parameter list</i><b>)
+{</b> <i>statements</i> <b>}</b></p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>
+first reads the program source from the
+<i>program-file</i>(s) if specified, from arguments to
+<b>&minus;&minus;source</b>, or from the first non-option
+argument on the command line. The <b>&minus;f</b> and
+<b>&minus;&minus;source</b> options may be used multiple
+times on the command line. <i>Gawk</i> reads the program
+text as if all the <i>program-file</i>s and command line
+source texts had been concatenated together. This is useful
+for building libraries of <small>AWK</small> functions,
+without having to include them in each new
+<small>AWK</small> program that uses them. It also provides
+the ability to mix library functions with command line
+programs.</p>
+
+<p style="margin-left:11%; margin-top: 1em">In addition,
+lines beginning with <b>@include</b> may be used to include
+other source files into your program, making library use
+even easier.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The environment
+variable <b>AWKPATH</b> specifies a search path to use when
+finding source files named with the <b>&minus;f</b> option.
+If this variable does not exist, the default path is
+<b>&quot;.:/usr/local/share/awk&quot;</b>. (The actual
+directory may vary, depending upon how <i>gawk</i> was built
+and installed.) If a file name given to the <b>&minus;f</b>
+option contains a &ldquo;/&rdquo; character, no path search
+is performed.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>
+executes <small>AWK</small> programs in the following order.
+First, all variable assignments specified via the
+<b>&minus;v</b> option are performed. Next, <i>gawk</i>
+compiles the program into an internal form. Then,
+<i>gawk</i> executes the code in the <b>BEGIN</b> block(s)
+(if any), and then proceeds to read each file named in the
+<b>ARGV</b> array (up to <b>ARGV[ARGC]</b>). If there are no
+files named on the command line, <i>gawk</i> reads the
+standard input.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If a filename
+on the command line has the form
+<i>var</i><b>=</b><i>val</i> it is treated as a variable
+assignment. The variable <i>var</i> will be assigned the
+value <i>val</i>. (This happens after any <b>BEGIN</b>
+block(s) have been run.) Command line variable assignment is
+most useful for dynamically assigning values to the
+variables <small>AWK</small> uses to control how input is
+broken into fields and records. It is also useful for
+controlling state if multiple passes are needed over a
+single data file.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If the value of
+a particular element of <b>ARGV</b> is empty
+(<b>&quot;&quot;</b>), <i>gawk</i> skips over it.</p>
+
+<p style="margin-left:11%; margin-top: 1em">For each input
+file, if a <b>BEGINFILE</b> rule exists, <i>gawk</i>
+executes the associated code before processing the contents
+of the file. Similarly, <i>gawk</i> executes the code
+associated with <b>ENDFILE</b> after processing the
+file.</p>
+
+<p style="margin-left:11%; margin-top: 1em">For each record
+in the input, <i>gawk</i> tests to see if it matches any
+<i>pattern</i> in the <small>AWK</small> program. For each
+pattern that the record matches, the associated
+<i>action</i> is executed. The patterns are tested in the
+order they occur in the program.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Finally, after
+all the input is exhausted, <i>gawk</i> executes the code in
+the <b>END</b> block(s) (if any).</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Command Line
+Directories</b> <br>
+According to POSIX, files named on the <i>awk</i> command
+line must be text files. The behavior is
+&lsquo;&lsquo;undefined&rsquo;&rsquo; if they are not. Most
+versions of <i>awk</i> treat a directory on the command line
+as a fatal error.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Starting with
+version 4.0 of <i>gawk</i>, a directory on the command line
+produces a warning, but is otherwise skipped. If either of
+the <b>&minus;&minus;posix</b> or
+<b>&minus;&minus;traditional</b> options is given, then
+<i>gawk</i> reverts to treating directories on the command
+line as a fatal error.</p>
+
+<h2>VARIABLES, RECORDS AND FIELDS
+<a name="VARIABLES, RECORDS AND FIELDS"></a>
+</h2>
+
+
+
+<p style="margin-left:11%; margin-top: 1em"><small>AWK</small>
+variables are dynamic; they come into existence when they
+are first used. Their values are either floating-point
+numbers or strings, or both, depending upon how they are
+used. <small>AWK</small> also has one dimensional arrays;
+arrays with multiple dimensions may be simulated. Several
+pre-defined variables are set as a program runs; these are
+described as needed and summarized below.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Records</b>
+<br>
+Normally, records are separated by newline characters. You
+can control how records are separated by assigning values to
+the built-in variable <b>RS</b>. If <b>RS</b> is any single
+character, that character separates records. Otherwise,
+<b>RS</b> is a regular expression. Text in the input that
+matches this regular expression separates the record.
+However, in compatibility mode, only the first character of
+its string value is used for separating records. If
+<b>RS</b> is set to the null string, then records are
+separated by blank lines. When <b>RS</b> is set to the null
+string, the newline character always acts as a field
+separator, in addition to whatever value <b>FS</b> may
+have.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Fields</b>
+<br>
+As each input record is read, <i>gawk</i> splits the record
+into <i>fields</i>, using the value of the <b>FS</b>
+variable as the field separator. If <b>FS</b> is a single
+character, fields are separated by that character. If
+<b>FS</b> is the null string, then each individual character
+becomes a separate field. Otherwise, <b>FS</b> is expected
+to be a full regular expression. In the special case that
+<b>FS</b> is a single space, fields are separated by runs of
+spaces and/or tabs and/or newlines. (But see the section
+<b>POSIX COMPATIBILITY</b>, below). <b>NOTE</b>: The value
+of <b>IGNORECASE</b> (see below) also affects how fields are
+split when <b>FS</b> is a regular expression, and how
+records are separated when <b>RS</b> is a regular
+expression.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If the
+<b>FIELDWIDTHS</b> variable is set to a space separated list
+of numbers, each field is expected to have fixed width, and
+<i>gawk</i> splits up the record using the specified widths.
+The value of <b>FS</b> is ignored. Assigning a new value to
+<b>FS</b> or <b>FPAT</b> overrides the use of
+<b>FIELDWIDTHS</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Similarly, if
+the <b>FPAT</b> variable is set to a string representing a
+regular expression, each field is made up of text that
+matches that regular expression. In this case, the regular
+expression describes the fields themselves, instead of the
+text that separates the fields. Assigning a new value to
+<b>FS</b> or <b>FIELDWIDTHS</b> overrides the use of
+<b>FPAT</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Each field in
+the input record may be referenced by its position,
+<b>$1</b>, <b>$2</b>, and so on. <b>$0</b> is the whole
+record. Fields need not be referenced by constants:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>n = 5 <br>
+print $n</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">prints the
+fifth field in the input record.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The variable
+<b>NF</b> is set to the total number of fields in the input
+record.</p>
+
+<p style="margin-left:11%; margin-top: 1em">References to
+non-existent fields (i.e. fields after <b>$NF</b>) produce
+the null-string. However, assigning to a non-existent field
+(e.g., <b>$(NF+2) = 5</b>) increases the value of <b>NF</b>,
+creates any intervening fields with the null string as their
+value, and causes the value of <b>$0</b> to be recomputed,
+with the fields being separated by the value of <b>OFS</b>.
+References to negative numbered fields cause a fatal error.
+Decrementing <b>NF</b> causes the values of fields past the
+new value to be lost, and the value of <b>$0</b> to be
+recomputed, with the fields being separated by the value of
+<b>OFS</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Assigning a
+value to an existing field causes the whole record to be
+rebuilt when <b>$0</b> is referenced. Similarly, assigning a
+value to <b>$0</b> causes the record to be resplit, creating
+new values for the fields.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Built-in
+Variables</b> <i><br>
+Gawk</i>&rsquo;s built-in variables are:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p style="margin-top: 1em"><b>ARGC</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p style="margin-top: 1em">The number of command line
+arguments (does not include options to <i>gawk</i>, or the
+program source).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>ARGIND</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The index in <b>ARGV</b> of the current file being
+processed.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>ARGV</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>Array of command line arguments. The array is indexed
+from 0 to <b>ARGC</b> &minus; 1. Dynamically changing the
+contents of <b>ARGV</b> can control the files used for
+data.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>BINMODE</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>On non-POSIX systems, specifies use of
+&ldquo;binary&rdquo; mode for all file I/O. Numeric values
+of 1, 2, or 3, specify that input files, output files, or
+all files, respectively, should use binary I/O. String
+values of <b>&quot;r&quot;</b>, or <b>&quot;w&quot;</b>
+specify that input files, or output files, respectively,
+should use binary I/O. String values of
+<b>&quot;rw&quot;</b> or <b>&quot;wr&quot;</b> specify that
+all files should use binary I/O. Any other string value is
+treated as <b>&quot;rw&quot;</b>, but generates a warning
+message.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>CONVFMT</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The conversion format for numbers,
+<b>&quot;%.6g&quot;</b>, by default.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>ENVIRON</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>An array containing the values of the current
+environment. The array is indexed by the environment
+variables, each element being the value of that variable
+(e.g., <b>ENVIRON[&quot;HOME&quot;]</b> might be
+<b>/home/arnold</b>). Changing this array does not affect
+the environment seen by programs which <i>gawk</i> spawns
+via redirection or the <b>system()</b> function.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>ERRNO</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>If a system error occurs either doing a redirection for
+<b>getline</b>, during a read for <b>getline</b>, or during
+a <b>close()</b>, then <b>ERRNO</b> will contain a string
+describing the error. The value is subject to translation in
+non-English locales.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>FIELDWIDTHS</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>A whitespace separated list of field widths. When set,
+<i>gawk</i> parses the input into fields of fixed width,
+instead of using the value of the <b>FS</b> variable as the
+field separator. See <b>Fields</b>, above.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>FILENAME</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The name of the current input file. If no files are
+specified on the command line, the value of <b>FILENAME</b>
+is &ldquo;&minus;&rdquo;. However, <b>FILENAME</b> is
+undefined inside the <b>BEGIN</b> block (unless set by
+<b>getline</b>).</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>FNR</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The input record number in the current input file.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>FPAT</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>A regular expression describing the contents of the
+fields in a record. When set, <i>gawk</i> parses the input
+into fields, where the fields match the regular expression,
+instead of using the value of the <b>FS</b> variable as the
+field separator. See <b>Fields</b>, above.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>FS</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The input field separator, a space by default. See
+<b>Fields</b>, above.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>IGNORECASE</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>Controls the case-sensitivity of all regular expression
+and string operations. If <b>IGNORECASE</b> has a non-zero
+value, then string comparisons and pattern matching in
+rules, field splitting with <b>FS</b> and <b>FPAT</b>,
+record separating with <b>RS</b>, regular expression
+matching with <b>~</b> and <b>!~</b>, and the
+<b>gensub()</b>, <b>gsub()</b>, <b>index()</b>,
+<b>match()</b>, <b>patsplit()</b>, <b>split()</b>, and
+<b>sub()</b> built-in functions all ignore case when doing
+regular expression operations. <b>NOTE</b>: Array
+subscripting is <i>not</i> affected. However, the
+<b>asort()</b> and <b>asorti()</b> functions are
+affected.</p> </td></tr>
+</table>
+
+<p style="margin-left:29%;">Thus, if <b>IGNORECASE</b> is
+not equal to zero, <b>/aB/</b> matches all of the strings
+<b>&quot;ab&quot;</b>, <b>&quot;aB&quot;</b>,
+<b>&quot;Ab&quot;</b>, and <b>&quot;AB&quot;</b>. As with
+all <small>AWK</small> variables, the initial value of
+<b>IGNORECASE</b> is zero, so all regular expression and
+string operations are normally case-sensitive.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p style="margin-top: 1em"><b>LINT</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p style="margin-top: 1em">Provides dynamic control of the
+<b>&minus;&minus;lint</b> option from within an
+<small>AWK</small> program. When true, <i>gawk</i> prints
+lint warnings. When false, it does not. When assigned the
+string value <b>&quot;fatal&quot;</b>, lint warnings become
+fatal errors, exactly like <b>&minus;&minus;lint=fatal</b>.
+Any other true value just prints warnings.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>NF</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The number of fields in the current input record.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>NR</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The total number of input records seen so far.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>OFMT</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The output format for numbers, <b>&quot;%.6g&quot;</b>,
+by default.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>OFS</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The output field separator, a space by default.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>ORS</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The output record separator, by default a newline.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="12%">
+
+
+<p><b>PROCINFO</b></p></td>
+<td width="6%"></td>
+<td width="71%">
+
+
+<p>The elements of this array provide access to information
+about the running <small>AWK</small> program. On some
+systems, there may be elements in the array,
+<b>&quot;group1&quot;</b> through
+<b>&quot;group</b><i>n</i><b>&quot;</b> for some <i>n</i>,
+which is the number of supplementary groups that the process
+has. Use the <b>in</b> operator to test for these elements.
+The following elements are guaranteed to be available:</p></td></tr>
+</table>
+
+
+<p style="margin-left:29%;"><b>PROCINFO[&quot;egid&quot;]</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="60%"></td>
+<td width="40%">
+
+
+<p style="margin-top: 1em">the value of the
+<i>getegid</i>(2) system call.</p></td></tr>
+</table>
+
+
+<p style="margin-left:29%;"><b>PROCINFO[&quot;strftime&quot;]</b></p>
+
+<p style="margin-left:60%;">The default time format string
+for <b>strftime()</b>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;euid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the value of the <i>geteuid</i>(2) system call.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;FS&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p><b>&quot;FS&quot;</b> if field splitting with <b>FS</b>
+is in effect, <b>&quot;FPAT&quot;</b> if field splitting
+with <b>FPAT</b> is in effect, or
+<b>&quot;FIELDWIDTHS&quot;</b> if field splitting with
+<b>FIELDWIDTHS</b> is in effect.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;gid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the value of the <i>getgid</i>(2) system call.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;pgrpid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the process group ID of the current process.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;pid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the process ID of the current process.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;ppid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the parent process ID of the current process.</p></td></tr>
+<tr valign="top" align="left">
+<td width="29%"></td>
+<td width="28%">
+
+
+<p><b>PROCINFO[&quot;uid&quot;]</b></p></td>
+<td width="3%"></td>
+<td width="40%">
+
+
+<p>the value of the <i>getuid</i>(2) system call.</p></td></tr>
+</table>
+
+
+<p style="margin-left:29%;"><b>PROCINFO[&quot;sorted_in&quot;]</b></p>
+
+<p style="margin-left:60%;">If this element exists in
+<b>PROCINFO</b>, then its value controls the order in which
+array elements are traversed in <b>for</b> loops. Supported
+values are <b>&quot;@ind_str_asc&quot;</b>,
+<b>&quot;@ind_num_asc&quot;</b>,
+<b>&quot;@val_type_asc&quot;</b>,
+<b>&quot;@val_str_asc&quot;</b>,
+<b>&quot;@val_num_asc&quot;</b>,
+<b>&quot;@ind_str_desc&quot;</b>,
+<b>&quot;@ind_num_desc&quot;</b>,
+<b>&quot;@val_type_desc&quot;</b>,
+<b>&quot;@val_str_desc&quot;</b>,
+<b>&quot;@val_num_desc&quot;</b>, and
+<b>&quot;@unsorted&quot;</b>. The value can also be the name
+of any comparison function defined as follows:</p>
+
+<p style="margin-left:40%; margin-top: 1em"><b>function
+cmp_func(i1, v1, i2, v2)</b></p>
+
+<p style="margin-left:29%; margin-top: 1em">where <i>i1</i>
+and <i>i2</i> are the indices, and <i>v1</i> and <i>v2</i>
+are the corresponding values of the two elements being
+compared. It should return a number less than, equal to, or
+greater than 0, depending on how the elements of the array
+are to be ordered. <b><br>
+PROCINFO[&quot;version&quot;]</b></p>
+
+<p style="margin-left:40%;">the version of <i>gawk</i>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>RS</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The input record separator, by default a newline.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>RT</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The record terminator. <i>Gawk</i> sets <b>RT</b> to the
+input text that matched the character or regular expression
+specified by <b>RS</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>RSTART</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The index of the first character matched by
+<b>match()</b>; 0 if no match. (This implies that character
+indices start at one.)</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>RLENGTH</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The length of the string matched by <b>match()</b>;
+&minus;1 if no match.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>SUBSEP</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The character used to separate multiple subscripts in
+array elements, by default <b>&quot;\034&quot;</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>TEXTDOMAIN</b></p></td>
+<td width="3%"></td>
+<td width="71%">
+
+
+<p>The text domain of the <small>AWK</small> program; used
+to find the localized translations for the program&rsquo;s
+strings.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Arrays</b>
+<br>
+Arrays are subscripted with an expression between square
+brackets (<b>[</b> and <b>]</b>). If the expression is an
+expression list (<i>expr</i>, <i>expr</i> ...) then the
+array subscript is a string consisting of the concatenation
+of the (string) value of each expression, separated by the
+value of the <b>SUBSEP</b> variable. This facility is used
+to simulate multiply dimensioned arrays. For example:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>i =
+&quot;A&quot;; j = &quot;B&quot;; k = &quot;C&quot; <br>
+x[i, j, k] = &quot;hello, world\n&quot;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">assigns the
+string <b>&quot;hello, world\n&quot;</b> to the element of
+the array <b>x</b> which is indexed by the string
+<b>&quot;A\034B\034C&quot;</b>. All arrays in
+<small>AWK</small> are associative, i.e. indexed by string
+values.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The special
+operator <b>in</b> may be used to test if an array has an
+index consisting of a particular value:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>if (val in
+array)</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>print array[val]</b></p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">If the array
+has multiple subscripts, use <b>(i, j) in array</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The <b>in</b>
+construct may also be used in a <b>for</b> loop to iterate
+over all the elements of an array.</p>
+
+<p style="margin-left:11%; margin-top: 1em">An element may
+be deleted from an array using the <b>delete</b> statement.
+The <b>delete</b> statement may also be used to delete the
+entire contents of an array, just by specifying the array
+name without a subscript.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>gawk</i>
+supports true multidimensional arrays. It does not require
+that such arrays be &lsquo;&lsquo;rectangular&rsquo;&rsquo;
+as in C or C++. For example:</p>
+
+<p style="margin-left:22%;"><b>a[1] = 5 <br>
+a[2][1] = 6 <br>
+a[2][2] = 7</b></p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Variable
+Typing And Conversion</b> <br>
+Variables and fields may be (floating point) numbers, or
+strings, or both. How the value of a variable is interpreted
+depends upon its context. If used in a numeric expression,
+it will be treated as a number; if used as a string it will
+be treated as a string.</p>
+
+<p style="margin-left:11%; margin-top: 1em">To force a
+variable to be treated as a number, add 0 to it; to force it
+to be treated as a string, concatenate it with the null
+string.</p>
+
+<p style="margin-left:11%; margin-top: 1em">When a string
+must be converted to a number, the conversion is
+accomplished using <i>strtod</i>(3). A number is converted
+to a string by using the value of <b>CONVFMT</b> as a format
+string for <i>sprintf</i>(3), with the numeric value of the
+variable as the argument. However, even though all numbers
+in <small>AWK</small> are floating-point, integral values
+are <i>always</i> converted as integers. Thus, given</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>CONVFMT =
+&quot;%2.2f&quot; <br>
+a = 12 <br>
+b = a &quot;&quot;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">the variable
+<b>b</b> has a string value of <b>&quot;12&quot;</b> and not
+<b>&quot;12.00&quot;</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>NOTE</b>:
+When operating in POSIX mode (such as with the
+<b>&minus;&minus;posix</b> command line option), beware that
+locale settings may interfere with the way decimal numbers
+are treated: the decimal separator of the numbers you are
+feeding to <i>gawk</i> must conform to what your locale
+would expect, be it a comma (,) or a period (.).</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i>
+performs comparisons as follows: If two variables are
+numeric, they are compared numerically. If one value is
+numeric and the other has a string value that is a
+&ldquo;numeric string,&rdquo; then comparisons are also done
+numerically. Otherwise, the numeric value is converted to a
+string and a string comparison is performed. Two strings are
+compared, of course, as strings.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Note that
+string constants, such as <b>&quot;57&quot;</b>, are
+<i>not</i> numeric strings, they are string constants. The
+idea of &ldquo;numeric string&rdquo; only applies to fields,
+<b>getline</b> input, <b>FILENAME</b>, <b>ARGV</b> elements,
+<b>ENVIRON</b> elements and the elements of an array created
+by <b>split()</b> or <b>patsplit()</b> that are numeric
+strings. The basic idea is that <i>user input</i>, and only
+user input, that looks numeric, should be treated that
+way.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Uninitialized
+variables have the numeric value 0 and the string value
+&quot;&quot; (the null, or empty, string).</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Octal and
+Hexadecimal Constants</b> <br>
+You may use C-style octal and hexadecimal constants in your
+AWK program source code. For example, the octal value
+<b>011</b> is equal to decimal <b>9</b>, and the hexadecimal
+value <b>0x11</b> is equal to decimal 17.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>String
+Constants</b> <br>
+String constants in <small>AWK</small> are sequences of
+characters enclosed between double quotes (like
+<b>&quot;value&quot;</b>). Within strings, certain <i>escape
+sequences</i> are recognized, as in C. These are:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p style="margin-top: 1em"><b>\\</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p style="margin-top: 1em">A literal backslash.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\a</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>The &ldquo;alert&rdquo; character; usually the
+<small>ASCII BEL</small> character.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\b</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>backspace.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\f</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>form-feed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\n</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>newline.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\r</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>carriage return.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\t</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>horizontal tab.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p><b>\v</b></p></td>
+<td width="4%"></td>
+<td width="82%">
+
+
+<p>vertical tab.</p></td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>\x</b><i>hex digits</i></p>
+
+<p style="margin-left:18%;">The character represented by
+the string of hexadecimal digits following the <b>\x</b>. As
+in <small>ANSI</small> C, all following hexadecimal digits
+are considered part of the escape sequence. (This feature
+should tell us something about language design by
+committee.) E.g., <b>&quot;\x1B&quot;</b> is the
+<small>ASCII ESC</small> (escape) character.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>\</b><i>ddd</i></p></td>
+<td width="1%"></td>
+<td width="82%">
+
+
+<p>The character represented by the 1-, 2-, or 3-digit
+sequence of octal digits. E.g., <b>&quot;\033&quot;</b> is
+the <small>ASCII ESC</small> (escape) character.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>\</b><i>c</i></p></td>
+<td width="1%"></td>
+<td width="82%">
+
+
+<p>The literal character <i>c</i>.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The escape
+sequences may also be used inside constant regular
+expressions (e.g., <b>/[&nbsp;\t\f\n\r\v]/</b> matches
+whitespace characters).</p>
+
+<p style="margin-left:11%; margin-top: 1em">In
+compatibility mode, the characters represented by octal and
+hexadecimal escape sequences are treated literally when used
+in regular expression constants. Thus, <b>/a\52b/</b> is
+equivalent to <b>/a\*b/</b>.</p>
+
+<h2>PATTERNS AND ACTIONS
+<a name="PATTERNS AND ACTIONS"></a>
+</h2>
+
+
+
+<p style="margin-left:11%; margin-top: 1em"><small>AWK</small>
+is a line-oriented language. The pattern comes first, and
+then the action. Action statements are enclosed in <b>{</b>
+and <b>}</b>. Either the pattern may be missing, or the
+action may be missing, but, of course, not both. If the
+pattern is missing, the action is executed for every single
+record of input. A missing action is equivalent to</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>{ print
+}</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">which prints
+the entire record.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Comments begin
+with the <b>#</b> character, and continue until the end of
+the line. Blank lines may be used to separate statements.
+Normally, a statement ends with a newline, however, this is
+not the case for lines ending in a comma, <b>{</b>,
+<b>?</b>, <b>:</b>, <b>&amp;&amp;</b>, or <b>||</b>. Lines
+ending in <b>do</b> or <b>else</b> also have their
+statements automatically continued on the following line. In
+other cases, a line can be continued by ending it with a
+&ldquo;\&rdquo;, in which case the newline is ignored.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Multiple
+statements may be put on one line by separating them with a
+&ldquo;;&rdquo;. This applies to both the statements within
+the action part of a pattern-action pair (the usual case),
+and to the pattern-action statements themselves.</p>
+
+
+<p style="margin-left:11%; margin-top: 1em"><b>Patterns</b>
+<small><br>
+AWK</small> patterns may be one of the following:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>BEGIN <br>
+END <br>
+BEGINFILE <br>
+ENDFILE <br>
+/</b><i>regular expression</i><b>/</b> <i><br>
+relational expression <br>
+pattern</i> <b>&amp;&amp;</b> <i>pattern <br>
+pattern</i> <b>||</b> <i>pattern <br>
+pattern</i> <b>?</b> <i>pattern</i> <b>:</b> <i>pattern</i>
+<b><br>
+(</b><i>pattern</i><b>) <br>
+!</b> <i>pattern <br>
+pattern1</i><b>,</b> <i>pattern2</i></p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>BEGIN</b>
+and <b>END</b> are two special kinds of patterns which are
+not tested against the input. The action parts of all
+<b>BEGIN</b> patterns are merged as if all the statements
+had been written in a single <b>BEGIN</b> block. They are
+executed before any of the input is read. Similarly, all the
+<b>END</b> blocks are merged, and executed when all the
+input is exhausted (or when an <b>exit</b> statement is
+executed). <b>BEGIN</b> and <b>END</b> patterns cannot be
+combined with other patterns in pattern expressions.
+<b>BEGIN</b> and <b>END</b> patterns cannot have missing
+action parts.</p>
+
+
+<p style="margin-left:11%; margin-top: 1em"><b>BEGINFILE</b>
+and <b>ENDFILE</b> are additional special patterns whose
+bodies are executed before reading the first record of each
+command line input file and after reading the last record of
+each file. Inside the <b>BEGINFILE</b> rule, the value of
+<b>ERRNO</b> will be the empty string if the file could be
+opened successfully. Otherwise, there is some problem with
+the file and the code should use <b>nextfile</b> to skip it.
+If that is not done, <i>gawk</i> produces its usual fatal
+error for files that cannot be opened.</p>
+
+<p style="margin-left:11%; margin-top: 1em">For
+<b>/</b><i>regular expression</i><b>/</b> patterns, the
+associated statement is executed for each input record that
+matches the regular expression. Regular expressions are the
+same as those in <i>egrep</i>(1), and are summarized
+below.</p>
+
+<p style="margin-left:11%; margin-top: 1em">A <i>relational
+expression</i> may use any of the operators defined below in
+the section on actions. These generally test whether certain
+fields match certain regular expressions.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The
+<b>&amp;&amp;</b>, <b>||</b>, and <b>!</b> operators are
+logical AND, logical OR, and logical NOT, respectively, as
+in C. They do short-circuit evaluation, also as in C, and
+are used for combining more primitive pattern expressions.
+As in most languages, parentheses may be used to change the
+order of evaluation.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The <b>?:</b>
+operator is like the same operator in C. If the first
+pattern is true then the pattern used for testing is the
+second pattern, otherwise it is the third. Only one of the
+second and third patterns is evaluated.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The
+<i>pattern1</i><b>,</b> <i>pattern2</i> form of an
+expression is called a <i>range pattern</i>. It matches all
+input records starting with a record that matches
+<i>pattern1</i>, and continuing until a record that matches
+<i>pattern2</i>, inclusive. It does not combine with any
+other sort of pattern expression.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Regular
+Expressions</b> <br>
+Regular expressions are the extended kind found in
+<i>egrep</i>. They are composed of characters as
+follows:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p style="margin-top: 1em"><i>c</i></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p style="margin-top: 1em">matches the non-metacharacter
+<i>c</i>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>\c</i></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the literal character <i>c</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>.</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches any character <i>including</i> newline.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>^</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the beginning of a string.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>$</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the end of a string.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>[</b><i>abc...</i><b>]</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>character list, matches any of the characters
+<i>abc...</i>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>[^</b><i>abc...</i><b>]</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>negated character list, matches any character except
+<i>abc...</i>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r1</i><b>|</b><i>r2</i></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>alternation: matches either <i>r1</i> or <i>r2</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r1r2</i></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>concatenation: matches <i>r1</i>, and then
+<i>r2</i>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>+</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches one or more <i>r</i>&rsquo;s.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>*</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches zero or more <i>r</i>&rsquo;s.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>?</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches zero or one <i>r</i>&rsquo;s.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>(</b><i>r</i><b>)</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>grouping: matches <i>r</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>{</b><i>n</i><b>}</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>{</b><i>n</i><b>,}</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><i>r</i><b>{</b><i>n</i><b>,</b><i>m</i><b>}</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>One or two numbers inside braces denote an <i>interval
+expression</i>. If there is one number in the braces, the
+preceding regular expression <i>r</i> is repeated <i>n</i>
+times. If there are two numbers separated by a comma,
+<i>r</i> is repeated <i>n</i> to <i>m</i> times. If there is
+one number followed by a comma, then <i>r</i> is repeated at
+least <i>n</i> times.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\y</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string at either the beginning or the
+end of a word.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\B</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string within a word.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\&lt;</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string at the beginning of a word.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\&gt;</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string at the end of a word.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\s</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches any whitespace character.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\S</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches any nonwhitespace character.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\w</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches any word-constituent character (letter, digit,
+or underscore).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\W</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches any character that is not word-constituent.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\&lsquo;</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string at the beginning of a buffer
+(string).</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>\&rsquo;</b></p></td>
+<td width="3%"></td>
+<td width="72%">
+
+
+<p>matches the empty string at the end of a buffer.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The escape
+sequences that are valid in string constants (see below) are
+also valid in regular expressions.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Character
+classes</i> are a feature introduced in the
+<small>POSIX</small> standard. A character class is a
+special notation for describing lists of characters that
+have a specific attribute, but where the actual characters
+themselves can vary from country to country and/or from
+character set to character set. For example, the notion of
+what is an alphabetic character differs in the USA and in
+France.</p>
+
+<p style="margin-left:11%; margin-top: 1em">A character
+class is only valid in a regular expression <i>inside</i>
+the brackets of a character list. Character classes consist
+of <b>[:</b>, a keyword denoting the class, and <b>:]</b>.
+The character classes defined by the <small>POSIX</small>
+standard are:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p style="margin-top: 1em"><b>[:alnum:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p style="margin-top: 1em">Alphanumeric characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:alpha:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Alphabetic characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:blank:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Space or tab characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:cntrl:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Control characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:digit:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Numeric characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:graph:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Characters that are both printable and visible. (A space
+is printable, but not visible, while an <b>a</b> is
+both.)</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:lower:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Lowercase alphabetic characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:print:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Printable characters (characters that are not control
+characters.)</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:punct:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Punctuation characters (characters that are not letter,
+digits, control characters, or space characters).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:space:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Space characters (such as space, tab, and formfeed, to
+name a few).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:upper:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Uppercase alphabetic characters.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="15%">
+
+
+<p><b>[:xdigit:]</b></p></td>
+<td width="2%"></td>
+<td width="72%">
+
+
+<p>Characters that are hexadecimal digits.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">For example,
+before the <small>POSIX</small> standard, to match
+alphanumeric characters, you would have had to write
+<b>/[A&minus;Za&minus;z0&minus;9]/</b>. If your character
+set had other alphabetic characters in it, this would not
+match them, and if your character set collated differently
+from <small>ASCII</small> , this might not even match the
+<small>ASCII</small> alphanumeric characters. With the
+<small>POSIX</small> character classes, you can write
+<b>/[[:alnum:]]/</b>, and this matches the alphabetic and
+numeric characters in your character set, no matter what it
+is.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Two additional
+special sequences can appear in character lists. These apply
+to non- <small>ASCII</small> character sets, which can have
+single symbols (called <i>collating elements</i>) that are
+represented with more than one character, as well as several
+characters that are equivalent for <i>collating</i>, or
+sorting, purposes. (E.g., in French, a plain &ldquo;e&rdquo;
+and a grave-accented &ldquo;`&rdquo; are equivalent.) <br>
+Collating Symbols</p>
+
+<p style="margin-left:22%;">A collating symbol is a
+multi-character collating element enclosed in <b>[.</b> and
+<b>.]</b>. For example, if <b>ch</b> is a collating element,
+then <b>[[.ch.]]</b> is a regular expression that matches
+this collating element, while <b>[ch]</b> is a regular
+expression that matches either <b>c</b> or <b>h</b>.</p>
+
+<p style="margin-left:11%;">Equivalence Classes</p>
+
+<p style="margin-left:22%;">An equivalence class is a
+locale-specific name for a list of characters that are
+equivalent. The name is enclosed in <b>[=</b> and <b>=]</b>.
+For example, the name <b>e</b> might be used to represent
+all of &ldquo;e,&rdquo; &ldquo;&acute;,&rdquo; and
+&ldquo;`.&rdquo; In this case, <b>[[=e=]]</b> is a regular
+expression that matches any of <b>e</b>, <b>&acute;</b>, or
+<b>`</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">These features
+are very valuable in non-English speaking locales. The
+library functions that <i>gawk</i> uses for regular
+expression matching currently only recognize
+<small>POSIX</small> character classes; they do not
+recognize collating symbols or equivalence classes.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The <b>\y</b>,
+<b>\B</b>, <b>\&lt;</b>, <b>\&gt;</b>, <b>\s</b>, <b>\S</b>,
+<b>\w</b>, <b>\W</b>, <b>\&lsquo;</b>, and <b>\&rsquo;</b>
+operators are specific to <i>gawk</i>; they are extensions
+based on facilities in the <small>GNU</small> regular
+expression libraries.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The various
+command line options control how <i>gawk</i> interprets
+characters in regular expressions. <br>
+No options</p>
+
+<p style="margin-left:22%;">In the default case,
+<i>gawk</i> provide all the facilities of
+<small>POSIX</small> regular expressions and the
+<small>GNU</small> regular expression operators described
+above.</p>
+
+<p style="margin-left:11%;"><b>&minus;&minus;posix</b></p>
+
+<p style="margin-left:22%;">Only <small>POSIX</small>
+regular expressions are supported, the <small>GNU</small>
+operators are not special. (E.g., <b>\w</b> matches a
+literal <b>w</b>).</p>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;traditional</b></p>
+
+<p style="margin-left:22%;">Traditional Unix <i>awk</i>
+regular expressions are matched. The <small>GNU</small>
+operators are not special, and interval expressions are not
+available. Characters described by octal and hexadecimal
+escape sequences are treated literally, even if they
+represent regular expression metacharacters.</p>
+
+
+<p style="margin-left:11%;"><b>&minus;&minus;re&minus;interval</b></p>
+
+<p style="margin-left:22%;">Allow interval expressions in
+regular expressions, even if
+<b>&minus;&minus;traditional</b> has been provided.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Actions</b>
+<br>
+Action statements are enclosed in braces, <b>{</b> and
+<b>}</b>. Action statements consist of the usual assignment,
+conditional, and looping statements found in most languages.
+The operators, control statements, and input/output
+statements available are patterned after those in C.</p>
+
+
+<p style="margin-left:11%; margin-top: 1em"><b>Operators</b>
+<br>
+The operators in <small>AWK</small> , in order of decreasing
+precedence, are</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>(</b>...<b>)</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Grouping</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>$</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Field reference.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>++ &minus;&minus;</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Increment and decrement, both prefix and postfix.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>^</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Exponentiation (<b>**</b> may also be used, and
+<b>**=</b> for the assignment operator).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>+ &minus; !</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Unary plus, unary minus, and logical negation.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>* / %</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Multiplication, division, and modulus.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>+ &minus;</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Addition and subtraction.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><i>space</i></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>String concatenation.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>| |&amp;</b></p></td>
+<td width="9%"></td>
+<td width="71%">
+
+
+<p>Piped I/O for <b>getline</b>, <b>print</b>, and
+<b>printf</b>.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>&lt; &gt; &lt;= &gt;= !=
+==</b></p>
+
+<p style="margin-left:29%;">The regular relational
+operators.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>~ !~</b></p></td>
+<td width="12%"></td>
+<td width="71%">
+
+
+<p>Regular expression match, negated match. <b>NOTE</b>: Do
+not use a constant regular expression (<b>/foo/</b>) on the
+left-hand side of a <b>~</b> or <b>!~</b>. Only use one on
+the right-hand side. The expression <b>/foo/ ~</b>
+<i>exp</i> has the same meaning as <b>(($0 ~ /foo/) ~</b>
+<i>exp</i><b>)</b>. This is usually <i>not</i> what was
+intended.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>in</b></p></td>
+<td width="12%"></td>
+<td width="71%">
+
+
+<p>Array membership.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>&amp;&amp;</b></p></td>
+<td width="12%"></td>
+<td width="71%">
+
+
+<p>Logical AND.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>||</b></p></td>
+<td width="12%"></td>
+<td width="71%">
+
+
+<p>Logical OR.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="6%">
+
+
+<p><b>?:</b></p></td>
+<td width="12%"></td>
+<td width="71%">
+
+
+<p>The C conditional expression. This has the form
+<i>expr1</i> <b>?</b> <i>expr2</i> <b>:</b> <i>expr3</i>. If
+<i>expr1</i> is true, the value of the expression is
+<i>expr2</i>, otherwise it is <i>expr3</i>. Only one of
+<i>expr2</i> and <i>expr3</i> is evaluated.</p></td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>= += &minus;= *= /= %=
+^=</b></p>
+
+<p style="margin-left:29%;">Assignment. Both absolute
+assignment <b>(</b><i>var</i> <b>=</b> <i>value</i><b>)</b>
+and operator-assignment (the other forms) are supported.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Control
+Statements</b> <br>
+The control statements are as follows:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>if
+(</b><i>condition</i><b>)</b> <i>statement</i> [ <b>else</b>
+<i>statement</i> ] <b><br>
+while (</b><i>condition</i><b>)</b> <i>statement</i> <b><br>
+do</b> <i>statement</i> <b>while (</b><i>condition</i><b>)
+<br>
+for (</b><i>expr1</i><b>;</b> <i>expr2</i><b>;</b>
+<i>expr3</i><b>)</b> <i>statement</i> <b><br>
+for (</b><i>var</i> <b>in</b> <i>array</i><b>)</b>
+<i>statement</i> <b><br>
+break <br>
+continue <br>
+delete</b> <i>array</i><b>[</b><i>index</i><b>] <br>
+delete</b> <i>array</i> <b><br>
+exit</b> [ <i>expression</i> ] <b><br>
+{</b> <i>statements</i> <b>} <br>
+switch (</b><i>expression</i><b>) { <br>
+case</b> <i>value</i><b>|</b><i>regex</i> <b>:</b>
+<i>statement <br>
+...</i> <br>
+[ <b>default:</b> <i>statement</i> ] <b><br>
+}</b></p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>I/O
+Statements</b> <br>
+The input/output statements are as follows:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="29%">
+
+
+<p><b>close(</b><i>file</i> [<b>,</b>
+<i>how</i>]<b>)</b></p> </td>
+<td width="5%"></td>
+<td width="55%">
+
+
+<p>Close file, pipe or co-process. The optional <i>how</i>
+should only be used when closing one end of a two-way pipe
+to a co-process. It must be a string value, either
+<b>&quot;to&quot;</b> or <b>&quot;from&quot;</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="29%">
+
+
+<p><b>getline</b></p></td>
+<td width="5%"></td>
+<td width="55%">
+
+
+<p>Set <b>$0</b> from next input record; set <b>NF</b>,
+<b>NR</b>, <b>FNR</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="29%">
+
+
+<p><b>getline &lt;</b><i>file</i></p></td>
+<td width="5%"></td>
+<td width="55%">
+
+
+<p>Set <b>$0</b> from next record of <i>file</i>; set
+<b>NF</b>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="29%">
+
+
+<p><b>getline</b> <i>var</i></p></td>
+<td width="5%"></td>
+<td width="55%">
+
+
+<p>Set <i>var</i> from next input record; set <b>NR</b>,
+<b>FNR</b>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="29%">
+
+
+<p><b>getline</b> <i>var</i> <b>&lt;</b><i>file</i></p></td>
+<td width="5%"></td>
+<td width="55%">
+
+
+<p>Set <i>var</i> from next record of <i>file</i>.</p></td></tr>
+</table>
+
+<p style="margin-left:11%;"><i>command</i> <b>| getline</b>
+[<i>var</i>]</p>
+
+<p style="margin-left:45%;">Run <i>command</i> piping the
+output either into <b>$0</b> or <i>var</i>, as above.</p>
+
+<p style="margin-left:11%;"><i>command</i> <b>|&amp;
+getline</b> [<i>var</i>]</p>
+
+<p style="margin-left:45%;">Run <i>command</i> as a
+co-process piping the output either into <b>$0</b> or
+<i>var</i>, as above. Co-processes are a <i>gawk</i>
+extension. (<i>command</i> can also be a socket. See the
+subsection <b>Special File Names</b>, below.)</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>next</b></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Stop processing the current input record. The next input
+record is read and processing starts over with the first
+pattern in the <small>AWK</small> program. If the end of the
+input data is reached, the <b>END</b> block(s), if any, are
+executed.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>nextfile</b></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Stop processing the current input file. The next input
+record read comes from the next input file. <b>FILENAME</b>
+and <b>ARGIND</b> are updated, <b>FNR</b> is reset to 1, and
+processing starts over with the first pattern in the
+<small>AWK</small> program. If the end of the input data is
+reached, the <b>END</b> block(s), if any, are executed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>print</b></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Print the current record. The output record is
+terminated with the value of the <b>ORS</b> variable.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>print</b> <i>expr-list</i></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Print expressions. Each expression is separated by the
+value of the <b>OFS</b> variable. The output record is
+terminated with the value of the <b>ORS</b> variable.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>print</b> <i>expr-list</i> <b>&gt;</b><i>file</i></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Print expressions on <i>file</i>. Each expression is
+separated by the value of the <b>OFS</b> variable. The
+output record is terminated with the value of the <b>ORS</b>
+variable.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>printf</b> <i>fmt, expr-list</i></p></td>
+<td width="2%"></td>
+<td width="55%">
+
+
+<p>Format and print. See <b>The</b> <i>printf</i>
+<b>Statement</b>, below.</p></td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>printf</b> <i>fmt,
+expr-list</i> <b>&gt;</b><i>file</i></p>
+
+<p style="margin-left:45%;">Format and print on
+<i>file</i>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="24%">
+
+
+<p><b>system(</b><i>cmd-line</i><b>)</b></p></td>
+<td width="10%"></td>
+<td width="55%">
+
+
+<p>Execute the command <i>cmd-line</i>, and return the exit
+status. (This may not be available on non-
+<small>POSIX</small> systems.)</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="24%">
+
+
+<p><b>fflush(</b>[<i>file</i>]<b>)</b></p></td>
+<td width="10%"></td>
+<td width="55%">
+
+
+<p>Flush any buffers associated with the open output file
+or pipe <i>file</i>. If <i>file</i> is missing or if it is
+the null string, then flush all open output files and
+pipes.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Additional
+output redirections are allowed for <b>print</b> and
+<b>printf</b>. <b><br>
+print ... &gt;&gt;</b> <i>file</i></p>
+
+<p style="margin-left:22%;">Appends output to the
+<i>file</i>.</p>
+
+<p style="margin-left:11%;"><b>print ... |</b>
+<i>command</i></p>
+
+<p style="margin-left:22%;">Writes on a pipe.</p>
+
+<p style="margin-left:11%;"><b>print ... |&amp;</b>
+<i>command</i></p>
+
+<p style="margin-left:22%;">Sends data to a co-process or
+socket. (See also the subsection <b>Special File Names</b>,
+below.)</p>
+
+<p style="margin-left:11%; margin-top: 1em">The
+<b>getline</b> command returns 1 on success, 0 on end of
+file, and &minus;1 on an error. Upon an error, <b>ERRNO</b>
+contains a string describing the problem.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>NOTE</b>:
+Failure in opening a two-way socket will result in a
+non-fatal error being returned to the calling function. If
+using a pipe, co-process, or socket to <b>getline</b>, or
+from <b>print</b> or <b>printf</b> within a loop, you
+<i>must</i> use <b>close()</b> to create new instances of
+the command or socket. <small>AWK</small> does not
+automatically close pipes, sockets, or co-processes when
+they return EOF.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>The</b>
+<i>printf</i> <b>Statement</b> <br>
+The <small>AWK</small> versions of the <b>printf</b>
+statement and <b>sprintf()</b> function (see below) accept
+the following conversion specification formats:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%c</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A single character. If the argument used for <b>%c</b>
+is numeric, it is treated as a character and printed.
+Otherwise, the argument is assumed to be a string, and the
+only first character of that string is printed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%d</b>, <b>%i</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A decimal number (the integer part).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%e</b>, <b>%E</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A floating point number of the form
+<b>[&minus;]d.dddddde[+&minus;]dd</b>. The <b>%E</b> format
+uses <b>E</b> instead of <b>e</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%f</b>, <b>%F</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A floating point number of the form
+<b>[&minus;]ddd.dddddd</b>. If the system library supports
+it, <b>%F</b> is available as well. This is like <b>%f</b>,
+but uses capital letters for special &ldquo;not a
+number&rdquo; and &ldquo;infinity&rdquo; values. If
+<b>%F</b> is not available, <i>gawk</i> uses <b>%f</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%g</b>, <b>%G</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>Use <b>%e</b> or <b>%f</b> conversion, whichever is
+shorter, with nonsignificant zeros suppressed. The <b>%G</b>
+format uses <b>%E</b> instead of <b>%e</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%o</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>An unsigned octal number (also an integer).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%u</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>An unsigned decimal number (again, an integer).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%s</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A character string.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%x</b>, <b>%X</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>An unsigned hexadecimal number (an integer). The
+<b>%X</b> format uses <b>ABCDEF</b> instead of
+<b>abcdef</b>.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>%%</b></p></td>
+<td width="3%"></td>
+<td width="77%">
+
+
+<p>A single <b>%</b> character; no argument is
+converted.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Optional,
+additional parameters may lie between the <b>%</b> and the
+control letter:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p style="margin-top: 1em"><i>count</i><b>$</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p style="margin-top: 1em">Use the <i>count</i>&rsquo;th
+argument at this point in the formatting. This is called a
+<i>positional specifier</i> and is intended primarily for
+use in translated versions of format strings, not in the
+original text of an AWK program. It is a <i>gawk</i>
+extension.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>&minus;</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>The expression should be left-justified within its
+field.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><i>space</i></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>For numeric conversions, prefix positive values with a
+space, and negative values with a minus sign.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>+</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>The plus sign, used before the width modifier (see
+below), says to always supply a sign for numeric
+conversions, even if the data to be formatted is positive.
+The <b>+</b> overrides the space modifier.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>#</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>Use an &ldquo;alternate form&rdquo; for certain control
+letters. For <b>%o</b>, supply a leading zero. For
+<b>%x</b>, and <b>%X</b>, supply a leading <b>0x</b> or
+<b>0X</b> for a nonzero result. For <b>%e</b>, <b>%E</b>,
+<b>%f</b> and <b>%F</b>, the result always contains a
+decimal point. For <b>%g</b>, and <b>%G</b>, trailing zeros
+are not removed from the result.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>0</b></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>A leading <b>0</b> (zero) acts as a flag, that indicates
+output should be padded with zeroes instead of spaces. This
+applies only to the numeric output formats. This flag only
+has an effect when the field width is wider than the value
+to be printed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><i>width</i></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>The field should be padded to this width. The field is
+normally padded with spaces. If the <b>0</b> flag has been
+used, it is padded with zeroes.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="9%">
+
+
+<p><b>.</b><i>prec</i></p></td>
+<td width="2%"></td>
+<td width="78%">
+
+
+<p>A number that specifies the precision to use when
+printing. For the <b>%e</b>, <b>%E</b>, <b>%f</b> and
+<b>%F</b>, formats, this specifies the number of digits you
+want printed to the right of the decimal point. For the
+<b>%g</b>, and <b>%G</b> formats, it specifies the maximum
+number of significant digits. For the <b>%d</b>, <b>%i</b>,
+<b>%o</b>, <b>%u</b>, <b>%x</b>, and <b>%X</b> formats, it
+specifies the minimum number of digits to print. For
+<b>%s</b>, it specifies the maximum number of characters
+from the string that should be printed.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The dynamic
+<i>width</i> and <i>prec</i> capabilities of the
+<small>ANSI</small> C <b>printf()</b> routines are
+supported. A <b>*</b> in place of either the <b>width</b> or
+<b>prec</b> specifications causes their values to be taken
+from the argument list to <b>printf</b> or <b>sprintf()</b>.
+To use a positional specifier with a dynamic width or
+precision, supply the <i>count</i><b>$</b> after the
+<b>*</b> in the format string. For example,
+<b>&quot;%3$*2$.*1$s&quot;</b>.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Special File
+Names</b> <br>
+When doing I/O redirection from either <b>print</b> or
+<b>printf</b> into a file, or via <b>getline</b> from a
+file, <i>gawk</i> recognizes certain special filenames
+internally. These filenames allow access to open file
+descriptors inherited from <i>gawk</i>&rsquo;s parent
+process (usually the shell). These file names may also be
+used on the command line to name data files. The filenames
+are:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p style="margin-top: 1em"><b>/dev/stdin</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p style="margin-top: 1em">The standard input.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>/dev/stdout</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The standard output.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>/dev/stderr</b></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The standard error output.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="17%">
+
+
+<p><b>/dev/fd/</b><i>n</i></p></td>
+<td width="1%"></td>
+<td width="71%">
+
+
+<p>The file associated with the open file descriptor
+<i>n</i>.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">These are
+particularly useful for error messages. For example:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>print
+&quot;You blew it!&quot; &gt;
+&quot;/dev/stderr&quot;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">whereas you
+would otherwise have to use</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>print
+&quot;You blew it!&quot; | &quot;cat
+1&gt;&amp;2&quot;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">The following
+special filenames may be used with the <b>|&amp;</b>
+co-process operator for creating TCP/IP network connections:
+<b><br>
+
+/inet/tcp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i>
+<b><br>
+
+/inet4/tcp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i>
+<b><br>
+
+/inet6/tcp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i></p>
+
+<p style="margin-left:22%;">Files for a TCP/IP connection
+on local port <i>lport</i> to remote host <i>rhost</i> on
+remote port <i>rport</i>. Use a port of <b>0</b> to have the
+system pick a port. Use <b>/inet4</b> to force an IPv4
+connection, and <b>/inet6</b> to force an IPv6 connection.
+Plain <b>/inet</b> uses the system default (most likely
+IPv4).</p>
+
+
+<p style="margin-left:11%;"><b>/inet/udp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i>
+<b><br>
+
+/inet4/udp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i>
+<b><br>
+
+/inet6/udp/</b><i>lport</i><b>/</b><i>rhost</i><b>/</b><i>rport</i></p>
+
+<p style="margin-left:22%;">Similar, but use UDP/IP instead
+of TCP/IP.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Numeric
+Functions</b> <small><br>
+AWK</small> has the following built-in arithmetic
+functions:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>atan2(</b><i>y</i><b>,</b> <i>x</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Return the arctangent of <i>y/x</i> in radians.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>cos(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Return the cosine of <i>expr</i>, which is in
+radians.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>exp(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>The exponential function.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>int(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Truncate to integer.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>log(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>The natural logarithm function.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>rand()</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Return a random number <i>N</i>, between 0 and 1, such
+that 0 &le; <i>N</i> &lt; 1.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>sin(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Return the sine of <i>expr</i>, which is in radians.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>sqrt(</b><i>expr</i><b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>The square root function.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="20%">
+
+
+<p><b>srand(</b>[<i>expr</i>]<b>)</b></p></td>
+<td width="1%"></td>
+<td width="68%">
+
+
+<p>Use <i>expr</i> as the new seed for the random number
+generator. If no <i>expr</i> is provided, use the time of
+day. The return value is the previous seed for the random
+number generator.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em"><b>String
+Functions</b> <i><br>
+Gawk</i> has the following built-in string functions:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p style="margin-top: 1em"><b>asort(</b><i>s</i> [<b>,</b>
+<i>d</i> [<b>,</b> <i>how</i>] ]<b>)</b></p></td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p style="margin-top: 1em">Return the number of elements in
+the source array <i>s</i>. Sort the contents of <i>s</i>
+using <i>gawk</i>&rsquo;s normal rules for comparing values,
+and replace the indices of the sorted values <i>s</i> with
+sequential integers starting with 1. If the optional
+destination array <i>d</i> is specified, then first
+duplicate <i>s</i> into <i>d</i>, and then sort <i>d</i>,
+leaving the indices of the source array <i>s</i> unchanged.
+The optional string <i>how</i> controls the direction and
+the comparison mode. Valid values for <i>how</i> are any of
+the strings valid for
+<b>PROCINFO[&quot;sorted_in&quot;]</b>. It can also be the
+name of a user-defined comparison function as described in
+<b>PROCINFO[&quot;sorted_in&quot;]</b>.</p> </td></tr>
+</table>
+
+<p style="margin-left:11%;"><b>asorti(</b><i>s</i>
+[<b>,</b> <i>d</i> [<b>,</b> <i>how</i>] ]<b>)</b></p>
+
+<p style="margin-left:48%;">Return the number of elements
+in the source array <i>s</i>. The behavior is the same as
+that of <b>asort()</b>, except that the array <i>indices</i>
+are used for sorting, not the array values. When done, the
+array is indexed numerically, and the values are those of
+the original indices. The original values are lost; thus
+provide a second array if you wish to preserve the original.
+The purpose of the optional string <i>how</i> is the same as
+described in <b>asort()</b> above.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>gensub(</b><i>r</i><b>,</b> <i>s</i><b>,</b> <i>h</i>
+[<b>,</b> <i>t</i>]<b>)</b></p></td>
+<td width="5%"></td>
+<td width="52%">
+
+
+<p>Search the target string <i>t</i> for matches of the
+regular expression <i>r</i>. If <i>h</i> is a string
+beginning with <b>g</b> or <b>G</b>, then replace all
+matches of <i>r</i> with <i>s</i>. Otherwise, <i>h</i> is a
+number indicating which match of <i>r</i> to replace. If
+<i>t</i> is not supplied, use <b>$0</b> instead. Within the
+replacement text <i>s</i>, the sequence <b>\</b><i>n</i>,
+where <i>n</i> is a digit from 1 to 9, may be used to
+indicate just the text that matched the <i>n</i>&rsquo;th
+parenthesized subexpression. The sequence <b>\0</b>
+represents the entire matched text, as does the character
+<b>&amp;</b>. Unlike <b>sub()</b> and <b>gsub()</b>, the
+modified string is returned as the result of the function,
+and the original target string is <i>not</i> changed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>gsub(</b><i>r</i><b>,</b> <i>s</i> [<b>,</b>
+<i>t</i>]<b>)</b></p> </td>
+<td width="5%"></td>
+<td width="52%">
+
+
+<p>For each substring matching the regular expression
+<i>r</i> in the string <i>t</i>, substitute the string
+<i>s</i>, and return the number of substitutions. If
+<i>t</i> is not supplied, use <b>$0</b>. An <b>&amp;</b> in
+the replacement text is replaced with the text that was
+actually matched. Use <b>\&amp;</b> to get a literal
+<b>&amp;</b>. (This must be typed as
+<b>&quot;\\&amp;&quot;</b>; see <i>GAWK: Effective AWK
+Programming</i> for a fuller discussion of the rules for
+<b>&amp;</b>&rsquo;s and backslashes in the replacement text
+of <b>sub()</b>, <b>gsub()</b>, and <b>gensub()</b>.)</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>index(</b><i>s</i><b>,</b> <i>t</i><b>)</b></p></td>
+<td width="5%"></td>
+<td width="52%">
+
+
+<p>Return the index of the string <i>t</i> in the string
+<i>s</i>, or 0 if <i>t</i> is not present. (This implies
+that character indices start at one.)</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>length(</b>[<i>s</i>]<b>)</b></p></td>
+<td width="5%"></td>
+<td width="52%">
+
+
+<p>Return the length of the string <i>s</i>, or the length
+of <b>$0</b> if <i>s</i> is not supplied. As a non-standard
+extension, with an array argument, <b>length()</b> returns
+the number of elements in the array.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="32%">
+
+
+<p><b>match(</b><i>s</i><b>,</b> <i>r</i> [<b>,</b>
+<i>a</i>]<b>)</b></p> </td>
+<td width="5%"></td>
+<td width="52%">
+
+
+<p>Return the position in <i>s</i> where the regular
+expression <i>r</i> occurs, or 0 if <i>r</i> is not present,
+and set the values of <b>RSTART</b> and <b>RLENGTH</b>. Note
+that the argument order is the same as for the <b>~</b>
+operator: <i>str</i> <b>~</b> <i>re</i>. If array <i>a</i>
+is provided, <i>a</i> is cleared and then elements 1 through
+<i>n</i> are filled with the portions of <i>s</i> that match
+the corresponding parenthesized subexpression in <i>r</i>.
+The 0&rsquo;th element of <i>a</i> contains the portion of
+<i>s</i> matched by the entire regular expression <i>r</i>.
+Subscripts <b>a[</b><i>n</i><b>, &quot;start&quot;]</b>, and
+<b>a[</b><i>n</i><b>, &quot;length&quot;]</b> provide the
+starting index in the string and length respectively, of
+each matching substring.</p></td></tr>
+</table>
+
+
+<p style="margin-left:11%;"><b>patsplit(</b><i>s</i><b>,</b>
+<i>a</i> [<b>,</b> <i>r</i> [<b>,</b> <i>seps</i>]
+]<b>)</b></p>
+
+<p style="margin-left:48%;">Split the string <i>s</i> into
+the array <i>a</i> and the separators array <i>seps</i> on
+the regular expression <i>r</i>, and return the number of
+fields. Element values are the portions of <i>s</i> that
+matched <i>r</i>. The value of <i>seps[i]</i> is the
+separator that appeared in front of <i>a[i+1]</i>. If
+<i>r</i> is omitted, <b>FPAT</b> is used instead. The arrays
+<i>a</i> and <i>seps</i> are cleared first. Splitting
+behaves identically to field splitting with <b>FPAT</b>,
+described above.</p>
+
+<p style="margin-left:11%;"><b>split(</b><i>s</i><b>,</b>
+<i>a</i> [<b>,</b> <i>r</i> [<b>,</b> <i>seps</i>]
+]<b>)</b></p>
+
+<p style="margin-left:48%;">Split the string <i>s</i> into
+the array <i>a</i> and the separators array <i>seps</i> on
+the regular expression <i>r</i>, and return the number of
+fields. If <i>r</i> is omitted, <b>FS</b> is used instead.
+The arrays <i>a</i> and <i>seps</i> are cleared first.
+<i>seps[i]</i> is the field separator matched by <i>r</i>
+between <i>a[i]</i> and <i>a[i+1]</i>. If <i>r</i> is a
+single space, then leading whitespace in <i>s</i> goes into
+the extra array element <i>seps[0]</i> and trailing
+whitespace goes into the extra array element <i>seps[n]</i>,
+where <i>n</i> is the return value of <i>split(s, a, r,
+seps)</i>. Splitting behaves identically to field splitting,
+described above.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>sprintf(</b><i>fmt</i><b>,</b>
+<i>expr-list</i><b>)</b></p> </td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Prints <i>expr-list</i> according to <i>fmt</i>, and
+returns the resulting string.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>strtonum(</b><i>str</i><b>)</b></p></td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Examine <i>str</i>, and return its numeric value. If
+<i>str</i> begins with a leading <b>0</b>, <b>strtonum()</b>
+assumes that <i>str</i> is an octal number. If <i>str</i>
+begins with a leading <b>0x</b> or <b>0X</b>,
+<b>strtonum()</b> assumes that <i>str</i> is a hexadecimal
+number. Otherwise, decimal is assumed.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>sub(</b><i>r</i><b>,</b> <i>s</i> [<b>,</b>
+<i>t</i>]<b>)</b></p> </td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Just like <b>gsub()</b>, but replace only the first
+matching substring.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>substr(</b><i>s</i><b>,</b> <i>i</i> [<b>,</b>
+<i>n</i>]<b>)</b></p> </td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Return the at most <i>n</i>-character substring of
+<i>s</i> starting at <i>i</i>. If <i>n</i> is omitted, use
+the rest of <i>s</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>tolower(</b><i>str</i><b>)</b></p></td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Return a copy of the string <i>str</i>, with all the
+uppercase characters in <i>str</i> translated to their
+corresponding lowercase counterparts. Non-alphabetic
+characters are left unchanged.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="35%">
+
+
+<p><b>toupper(</b><i>str</i><b>)</b></p></td>
+<td width="2%"></td>
+<td width="52%">
+
+
+<p>Return a copy of the string <i>str</i>, with all the
+lowercase characters in <i>str</i> translated to their
+corresponding uppercase counterparts. Non-alphabetic
+characters are left unchanged.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i> is
+multibyte aware. This means that <b>index()</b>,
+<b>length()</b>, <b>substr()</b> and <b>match()</b> all work
+in terms of characters, not bytes.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Time
+Functions</b> <br>
+Since one of the primary uses of <small>AWK</small> programs
+is processing log files that contain time stamp information,
+<i>gawk</i> provides the following functions for obtaining
+time stamps and formatting them. <b><br>
+mktime(</b><i>datespec</i><b>)</b></p>
+
+<p style="margin-left:26%;">Turn <i>datespec</i> into a
+time stamp of the same form as returned by <b>systime()</b>,
+and return the result. The <i>datespec</i> is a string of
+the form <i>YYYY MM DD HH MM SS[ DST]</i>. The contents of
+the string are six or seven numbers representing
+respectively the full year including century, the month from
+1 to 12, the day of the month from 1 to 31, the hour of the
+day from 0 to 23, the minute from 0 to 59, the second from 0
+to 60, and an optional daylight saving flag. The values of
+these numbers need not be within the ranges specified; for
+example, an hour of &minus;1 means 1 hour before midnight.
+The origin-zero Gregorian calendar is assumed, with year 0
+preceding year 1 and year &minus;1 preceding year 0. The
+time is assumed to be in the local timezone. If the daylight
+saving flag is positive, the time is assumed to be daylight
+saving time; if zero, the time is assumed to be standard
+time; and if negative (the default), <b>mktime()</b>
+attempts to determine whether daylight saving time is in
+effect for the specified time. If <i>datespec</i> does not
+contain enough elements or if the resulting time is out of
+range, <b>mktime()</b> returns &minus;1.</p>
+
+<p style="margin-left:11%;"><b>strftime(</b>[<i>format</i>
+[<b>,</b> <i>timestamp</i>[<b>,</b>
+<i>utc-flag</i>]]]<b>)</b></p>
+
+<p style="margin-left:26%;">Format <i>timestamp</i>
+according to the specification in <i>format</i>. If
+<i>utc-flag</i> is present and is non-zero or non-null, the
+result is in UTC, otherwise the result is in local time. The
+<i>timestamp</i> should be of the same form as returned by
+<b>systime()</b>. If <i>timestamp</i> is missing, the
+current time of day is used. If <i>format</i> is missing, a
+default format equivalent to the output of <i>date</i>(1) is
+used. The default format is available in
+<b>PROCINFO[&quot;strftime&quot;]</b>. See the specification
+for the <b>strftime()</b> function in <small>ANSI</small> C
+for the format conversions that are guaranteed to be
+available.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="14%">
+
+
+<p><b>systime()</b></p></td>
+<td width="1%"></td>
+<td width="74%">
+
+
+<p>Return the current time of day as the number of seconds
+since the Epoch (1970-01-01 00:00:00 UTC on
+<small>POSIX</small> systems).</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Bit
+Manipulations Functions</b> <i><br>
+Gawk</i> supplies the following bit manipulation functions.
+They work by converting double-precision floating point
+values to <b>uintmax_t</b> integers, doing the operation,
+and then converting the result back to floating point. The
+functions are:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p style="margin-top: 1em"><b>and(</b><i>v1</i><b>,</b>
+<i>v2</i><b>)</b></p> </td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p style="margin-top: 1em">Return the bitwise AND of the
+values provided by <i>v1</i> and <i>v2</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p><b>compl(</b><i>val</i><b>)</b></p></td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p>Return the bitwise complement of <i>val</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p><b>lshift(</b><i>val</i><b>,</b>
+<i>count</i><b>)</b></p> </td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p>Return the value of <i>val</i>, shifted left by
+<i>count</i> bits.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p><b>or(</b><i>v1</i><b>,</b> <i>v2</i><b>)</b></p></td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p>Return the bitwise OR of the values provided by
+<i>v1</i> and <i>v2</i>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p><b>rshift(</b><i>val</i><b>,</b>
+<i>count</i><b>)</b></p> </td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p>Return the value of <i>val</i>, shifted right by
+<i>count</i> bits.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="27%">
+
+
+<p><b>xor(</b><i>v1</i><b>,</b> <i>v2</i><b>)</b></p></td>
+<td width="4%"></td>
+<td width="58%">
+
+
+<p>Return the bitwise XOR of the values provided by
+<i>v1</i> and <i>v2</i>.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em"><b>Type
+Function</b> <br>
+The following function is for use with multidimensional
+arrays. <b><br>
+isarray(</b><i>x</i><b>)</b></p>
+
+<p style="margin-left:22%;">Return true if <i>x</i> is an
+array, false otherwise.</p>
+
+
+<p style="margin-left:11%; margin-top: 1em"><b>Internationalization
+Functions</b> <br>
+The following functions may be used from within your AWK
+program for translating strings at run-time. For full
+details, see <i>GAWK: Effective AWK Programming</i>. <b><br>
+bindtextdomain(</b><i>directory</i> [<b>,</b>
+<i>domain</i>]<b>)</b></p>
+
+<p style="margin-left:22%;">Specify the directory where
+<i>gawk</i> looks for the <b>.mo</b> files, in case they
+will not or cannot be placed in the
+&lsquo;&lsquo;standard&rsquo;&rsquo; locations (e.g., during
+testing). It returns the directory where <i>domain</i> is
+&lsquo;&lsquo;bound.&rsquo;&rsquo; <br>
+The default <i>domain</i> is the value of <b>TEXTDOMAIN</b>.
+If <i>directory</i> is the null string
+(<b>&quot;&quot;</b>), then <b>bindtextdomain()</b> returns
+the current binding for the given <i>domain</i>.</p>
+
+<p style="margin-left:11%;"><b>dcgettext(</b><i>string</i>
+[<b>,</b> <i>domain</i> [<b>,</b>
+<i>category</i>]]<b>)</b></p>
+
+<p style="margin-left:22%;">Return the translation of
+<i>string</i> in text domain <i>domain</i> for locale
+category <i>category</i>. The default value for
+<i>domain</i> is the current value of <b>TEXTDOMAIN</b>. The
+default value for <i>category</i> is
+<b>&quot;LC_MESSAGES&quot;</b>. <br>
+If you supply a value for <i>category</i>, it must be a
+string equal to one of the known locale categories described
+in <i>GAWK: Effective AWK Programming</i>. You must also
+supply a text domain. Use <b>TEXTDOMAIN</b> if you want to
+use the current domain.</p>
+
+
+<p style="margin-left:11%;"><b>dcngettext(</b><i>string1</i>
+, <i>string2</i> , <i>number</i> [<b>,</b> <i>domain</i>
+[<b>,</b> <i>category</i>]]<b>)</b></p>
+
+<p style="margin-left:22%;">Return the plural form used for
+<i>number</i> of the translation of <i>string1</i> and
+<i>string2</i> in text domain <i>domain</i> for locale
+category <i>category</i>. The default value for
+<i>domain</i> is the current value of <b>TEXTDOMAIN</b>. The
+default value for <i>category</i> is
+<b>&quot;LC_MESSAGES&quot;</b>. <br>
+If you supply a value for <i>category</i>, it must be a
+string equal to one of the known locale categories described
+in <i>GAWK: Effective AWK Programming</i>. You must also
+supply a text domain. Use <b>TEXTDOMAIN</b> if you want to
+use the current domain.</p>
+
+<h2>USER-DEFINED FUNCTIONS
+<a name="USER-DEFINED FUNCTIONS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">Functions in
+<small>AWK</small> are defined as follows:</p>
+
+
+<p style="margin-left:22%; margin-top: 1em"><b>function</b>
+<i>name</i><b>(</b><i>parameter list</i><b>) {</b>
+<i>statements</i> <b>}</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">Functions are
+executed when they are called from within expressions in
+either patterns or actions. Actual parameters supplied in
+the function call are used to instantiate the formal
+parameters declared in the function. Arrays are passed by
+reference, other variables are passed by value.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Since functions
+were not originally part of the <small>AWK</small> language,
+the provision for local variables is rather clumsy: They are
+declared as extra parameters in the parameter list. The
+convention is to separate local variables from real
+parameters by extra spaces in the parameter list. For
+example:</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>function
+f(p, q, a, b) # a and b are local <br>
+{</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="7%"></td>
+<td width="85%">
+
+
+<p><b>...</b></p></td></tr>
+</table>
+
+<p style="margin-left:22%;"><b>}</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%"></td>
+<td width="8%">
+
+
+<p><b>/abc/</b></p></td>
+<td width="77%">
+
+
+<p><b>{ ... ; f(1, 2) ; ... }</b></p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The left
+parenthesis in a function call is required to immediately
+follow the function name, without any intervening
+whitespace. This avoids a syntactic ambiguity with the
+concatenation operator. This restriction does not apply to
+the built-in functions listed above.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Functions may
+call each other and may be recursive. Function parameters
+used as local variables are initialized to the null string
+and the number zero upon function invocation.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Use
+<b>return</b> <i>expr</i> to return a value from a function.
+The return value is undefined if no value is provided, or if
+the function returns by &ldquo;falling off&rdquo; the
+end.</p>
+
+<p style="margin-left:11%; margin-top: 1em">As a
+<i>gawk</i> extension, functions may be called indirectly.
+To do this, assign the name of the function to be called, as
+a string, to a variable. Then use the variable as if it were
+the name of a function, prefixed with an <b>@</b> sign, like
+so:</p>
+
+<p style="margin-left:22%;"><b>function myfunc() <br>
+{</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>print &quot;myfunc called&quot;</b></p></td></tr>
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>...</b></p></td></tr>
+</table>
+
+<p style="margin-left:22%;"><b>}</b></p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+
+
+<p><b>{</b></p></td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+
+
+<p><b>...</b></p></td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+
+
+<p><b>the_func = &quot;myfunc&quot;</b></p></td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+</td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+</td></tr>
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+
+
+<p><b>@the_func()</b></p></td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+
+
+<p><b># call through the_func to myfunc</b></p></td></tr>
+<tr valign="top" align="left">
+<td width="22%"></td>
+<td width="-14%"></td>
+<td width="7%">
+
+
+<p><b>...</b></p></td>
+<td width="16%"></td>
+<td width="7%"></td>
+<td width="62%">
+</td></tr>
+</table>
+
+<p style="margin-left:22%;"><b>}</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">If
+<b>&minus;&minus;lint</b> has been provided, <i>gawk</i>
+warns about calls to undefined functions at parse time,
+instead of at run time. Calling an undefined function at run
+time is a fatal error.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The word
+<b>func</b> may be used in place of <b>function</b>.</p>
+
+<h2>DYNAMICALLY LOADING NEW FUNCTIONS
+<a name="DYNAMICALLY LOADING NEW FUNCTIONS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">You can
+dynamically add new built-in functions to the running
+<i>gawk</i> interpreter. The full details are beyond the
+scope of this manual page; see <i>GAWK: Effective AWK
+Programming</i> for the details. <b><br>
+extension(</b><i>object</i><b>,</b>
+<i>function</i><b>)</b></p>
+
+<p style="margin-left:23%;">Dynamically link the shared
+object file named by <i>object</i>, and invoke
+<i>function</i> in that object, to perform initialization.
+These should both be provided as strings. Return the value
+returned by <i>function</i>.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Using this
+feature at the C level is not pretty, but it is unlikely to
+go away. Additional mechanisms may be added at some
+point.</p>
+
+<h2>SIGNALS
+<a name="SIGNALS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>pgawk</i>
+accepts two signals. <b>SIGUSR1</b> causes it to dump a
+profile and function call stack to the profile file, which
+is either <b>awkprof.out</b>, or whatever file was named
+with the <b>&minus;&minus;profile</b> option. It then
+continues to run. <b>SIGHUP</b> causes <i>pgawk</i> to dump
+the profile and function call stack and then exit.</p>
+
+<h2>INTERNATIONALIZATION
+<a name="INTERNATIONALIZATION"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">String
+constants are sequences of characters enclosed in double
+quotes. In non-English speaking environments, it is possible
+to mark strings in the <small>AWK</small> program as
+requiring translation to the local natural language. Such
+strings are marked in the <small>AWK</small> program with a
+leading underscore (&ldquo;_&rdquo;). For example,</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>gawk
+&rsquo;BEGIN { print &quot;hello, world&quot;
+}&rsquo;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">always prints
+<b>hello, world</b>. But,</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>gawk
+&rsquo;BEGIN { print _&quot;hello, world&quot;
+}&rsquo;</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">might print
+<b>bonjour, monde</b> in France.</p>
+
+<p style="margin-left:11%; margin-top: 1em">There are
+several steps involved in producing and running a
+localizable <small>AWK</small> program.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p>1.</p></td>
+<td width="3%"></td>
+<td width="83%">
+
+
+<p>Add a <b>BEGIN</b> action to assign a value to the
+<b>TEXTDOMAIN</b> variable to set the text domain to a name
+associated with your program:</p></td></tr>
+</table>
+
+<p style="margin-left:17%; margin-top: 1em"><b>BEGIN {
+TEXTDOMAIN = &quot;myprog&quot; }</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">This allows
+<i>gawk</i> to find the <b>.mo</b> file associated with your
+program. Without this step, <i>gawk</i> uses the
+<b>messages</b> text domain, which likely does not contain
+translations for your program.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p style="margin-top: 1em">2.</p></td>
+<td width="3%"></td>
+<td width="83%">
+
+
+<p style="margin-top: 1em">Mark all strings that should be
+translated with leading underscores.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p>3.</p></td>
+<td width="3%"></td>
+<td width="83%">
+
+
+<p>If necessary, use the <b>dcgettext()</b> and/or
+<b>bindtextdomain()</b> functions in your program, as
+appropriate.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p>4.</p></td>
+<td width="3%"></td>
+<td width="83%">
+
+
+<p>Run <b>gawk &minus;&minus;gen&minus;pot &minus;f
+myprog.awk &gt; myprog.pot</b> to generate a <b>.po</b> file
+for your program.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="3%">
+
+
+<p>5.</p></td>
+<td width="3%"></td>
+<td width="83%">
+
+
+<p>Provide appropriate translations, and build and install
+the corresponding <b>.mo</b> files.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The
+internationalization features are described in full detail
+in <i>GAWK: Effective AWK Programming</i>.</p>
+
+<h2>POSIX COMPATIBILITY
+<a name="POSIX COMPATIBILITY"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">A primary goal
+for <i>gawk</i> is compatibility with the
+<small>POSIX</small> standard, as well as with the latest
+version of <small>UNIX</small> <i>awk</i>. To this end,
+<i>gawk</i> incorporates the following user visible features
+which are not described in the <small>AWK</small> book, but
+are part of the Bell Laboratories version of <i>awk</i>, and
+are in the <small>POSIX</small> standard.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The book
+indicates that command line variable assignment happens when
+<i>awk</i> would otherwise open the argument as a file,
+which is after the <b>BEGIN</b> block is executed. However,
+in earlier implementations, when such an assignment appeared
+before any file names, the assignment would happen
+<i>before</i> the <b>BEGIN</b> block was run. Applications
+came to depend on this &ldquo;feature.&rdquo; When
+<i>awk</i> was changed to match its documentation, the
+<b>&minus;v</b> option for assigning variables before
+program execution was added to accommodate applications that
+depended upon the old behavior. (This feature was agreed
+upon by both the Bell Laboratories and the
+<small>GNU</small> developers.)</p>
+
+<p style="margin-left:11%; margin-top: 1em">When processing
+arguments, <i>gawk</i> uses the special option
+&ldquo;&minus;&minus;&rdquo; to signal the end of arguments.
+In compatibility mode, it warns about but otherwise ignores
+undefined options. In normal operation, such arguments are
+passed on to the <small>AWK</small> program for it to
+process.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The
+<small>AWK</small> book does not define the return value of
+<b>srand()</b>. The <small>POSIX</small> standard has it
+return the seed it was using, to allow keeping track of
+random number sequences. Therefore <b>srand()</b> in
+<i>gawk</i> also returns its current seed.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Other new
+features are: The use of multiple <b>&minus;f</b> options
+(from MKS <i>awk</i>); the <b>ENVIRON</b> array; the
+<b>\a</b>, and <b>\v</b> escape sequences (done originally
+in <i>gawk</i> and fed back into the Bell Laboratories
+version); the <b>tolower()</b> and <b>toupper()</b> built-in
+functions (from the Bell Laboratories version); and the
+<small>ANSI</small> C conversion specifications in
+<b>printf</b> (done first in the Bell Laboratories
+version).</p>
+
+<h2>HISTORICAL FEATURES
+<a name="HISTORICAL FEATURES"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">There is one
+feature of historical <small>AWK</small> implementations
+that <i>gawk</i> supports: It is possible to call the
+<b>length()</b> built-in function not only with no argument,
+but even without parentheses! Thus,</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>a = length #
+Holy Algol 60, Batman!</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">is the same as
+either of</p>
+
+<p style="margin-left:22%; margin-top: 1em"><b>a = length()
+<br>
+a = length($0)</b></p>
+
+<p style="margin-left:11%; margin-top: 1em">Using this
+feature is poor practice, and <i>gawk</i> issues a warning
+about its use if <b>&minus;&minus;lint</b> is specified on
+the command line.</p>
+
+<h2>GNU EXTENSIONS
+<a name="GNU EXTENSIONS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>Gawk</i> has
+a number of extensions to <small>POSIX</small> <i>awk</i>.
+They are described in this section. All the extensions
+described here can be disabled by invoking <i>gawk</i> with
+the <b>&minus;&minus;traditional</b> or
+<b>&minus;&minus;posix</b> options.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The following
+features of <i>gawk</i> are not available in
+<small>POSIX</small> <i>awk</i>.</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p style="margin-top: 1em">&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p style="margin-top: 1em">No path search is performed for
+files named via the <b>&minus;f</b> option. Therefore the
+<b>AWKPATH</b> environment variable is not special.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>There is no facility for doing file inclusion
+(<i>gawk</i>&rsquo;s <b>@include</b> mechanism).</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>\x</b> escape sequence. (Disabled with
+<b>&minus;&minus;posix</b>.)</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The ability to continue lines after <b>?</b> and
+<b>:</b>. (Disabled with <b>&minus;&minus;posix</b>.)</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>Octal and hexadecimal constants in AWK programs.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>ARGIND</b>, <b>BINMODE</b>, <b>ERRNO</b>,
+<b>LINT</b>, <b>RT</b> and <b>TEXTDOMAIN</b> variables are
+not special.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>IGNORECASE</b> variable and its side-effects are
+not available.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>FIELDWIDTHS</b> variable and fixed-width field
+splitting.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>FPAT</b> variable and field splitting based on
+field values.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>PROCINFO</b> array is not available.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The use of <b>RS</b> as a regular expression.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The special file names available for I/O redirection are
+not recognized.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>|&amp;</b> operator for creating
+co-processes.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>BEGINFILE</b> and <b>ENDFILE</b> special patterns
+are not available.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The ability to split out individual characters using the
+null string as the value of <b>FS</b>, and as the third
+argument to <b>split()</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>An optional fourth argument to <b>split()</b> to receive
+the separator texts.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The optional second argument to the <b>close()</b>
+function.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The optional third argument to the <b>match()</b>
+function.</p> </td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The ability to use positional specifiers with
+<b>printf</b> and <b>sprintf()</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The ability to pass an array to <b>length()</b>.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The use of <b>delete</b> <i>array</i> to delete the
+entire contents of an array.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The use of <b>nextfile</b> to abandon processing of the
+current input file.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>The <b>and()</b>, <b>asort()</b>, <b>asorti()</b>,
+<b>bindtextdomain()</b>, <b>compl()</b>, <b>dcgettext()</b>,
+<b>dcngettext()</b>, <b>gensub()</b>, <b>lshift()</b>,
+<b>mktime()</b>, <b>or()</b>, <b>patsplit()</b>,
+<b>rshift()</b>, <b>strftime()</b>, <b>strtonum()</b>,
+<b>systime()</b> and <b>xor()</b> functions.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>Localizable strings.</p></td></tr>
+<tr valign="top" align="left">
+<td width="11%"></td>
+<td width="1%">
+
+
+<p>&bull;</p></td>
+<td width="2%"></td>
+<td width="86%">
+
+
+<p>Adding new built-in functions dynamically with the
+<b>extension()</b> function.</p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">The
+<small>AWK</small> book does not define the return value of
+the <b>close()</b> function. <i>Gawk</i>&rsquo;s
+<b>close()</b> returns the value from <i>fclose</i>(3), or
+<i>pclose</i>(3), when closing an output file or pipe,
+respectively. It returns the process&rsquo;s exit status
+when closing an input pipe. The return value is &minus;1 if
+the named file, pipe or co-process was not opened with a
+redirection.</p>
+
+<p style="margin-left:11%; margin-top: 1em">When
+<i>gawk</i> is invoked with the
+<b>&minus;&minus;traditional</b> option, if the <i>fs</i>
+argument to the <b>&minus;F</b> option is &ldquo;t&rdquo;,
+then <b>FS</b> is set to the tab character. Note that typing
+<b>gawk &minus;F\t ...</b> simply causes the shell to quote
+the &ldquo;t,&rdquo; and does not pass &ldquo;\t&rdquo; to
+the <b>&minus;F</b> option. Since this is a rather ugly
+special case, it is not the default behavior. This behavior
+also does not occur if <b>&minus;&minus;posix</b> has been
+specified. To really get a tab character as the field
+separator, it is best to use single quotes: <b>gawk
+&minus;F&rsquo;\t&rsquo; ...</b>.</p>
+
+<h2>ENVIRONMENT VARIABLES
+<a name="ENVIRONMENT VARIABLES"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">The
+<b>AWKPATH</b> environment variable can be used to provide a
+list of directories that <i>gawk</i> searches when looking
+for files named via the <b>&minus;f</b> and
+<b>&minus;&minus;file</b> options.</p>
+
+<p style="margin-left:11%; margin-top: 1em">For socket
+communication, two special environment variables can be used
+to control the number of retries (<b>GAWK_SOCK_RETRIES</b>),
+and the interval between retries (<b>GAWK_MSEC_SLEEP</b>).
+The interval is in milliseconds. On systems that do not
+support <i>usleep</i>(3), the value is rounded up to an
+integral number of seconds.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If
+<b>POSIXLY_CORRECT</b> exists in the environment, then
+<i>gawk</i> behaves exactly as if <b>&minus;&minus;posix</b>
+had been specified on the command line. If
+<b>&minus;&minus;lint</b> has been specified, <i>gawk</i>
+issues a warning message to this effect.</p>
+
+<h2>EXIT STATUS
+<a name="EXIT STATUS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">If the
+<b>exit</b> statement is used with a value, then <i>gawk</i>
+exits with the numeric value given to it.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Otherwise, if
+there were no problems during execution, <i>gawk</i> exits
+with the value of the C constant <b>EXIT_SUCCESS</b>. This
+is usually zero.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If an error
+occurs, <i>gawk</i> exits with the value of the C constant
+<b>EXIT_FAILURE</b>. This is usually one.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If <i>gawk</i>
+exits because of a fatal error, the exit status is 2. On
+non-POSIX systems, this value may be mapped to
+<b>EXIT_FAILURE</b>.</p>
+
+<h2>VERSION INFORMATION
+<a name="VERSION INFORMATION"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">This man page
+documents <i>gawk</i>, version 4.0.</p>
+
+<h2>AUTHORS
+<a name="AUTHORS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">The original
+version of <small>UNIX</small> <i>awk</i> was designed and
+implemented by Alfred Aho, Peter Weinberger, and Brian
+Kernighan of Bell Laboratories. Brian Kernighan continues to
+maintain and enhance it.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Paul Rubin and
+Jay Fenlason, of the Free Software Foundation, wrote
+<i>gawk</i>, to be compatible with the original version of
+<i>awk</i> distributed in Seventh Edition
+<small>UNIX</small> . John Woods contributed a number of bug
+fixes. David Trueman, with contributions from Arnold
+Robbins, made <i>gawk</i> compatible with the new version of
+<small>UNIX</small> <i>awk</i>. Arnold Robbins is the
+current maintainer.</p>
+
+<p style="margin-left:11%; margin-top: 1em">The initial DOS
+port was done by Conrad Kwok and Scott Garfinkle. Scott
+Deifik maintains the port to MS-DOS using DJGPP. Eli
+Zaretskii maintains the port to MS-Windows using MinGW. Pat
+Rankin did the port to VMS, and Michal Jaegermann did the
+port to the Atari ST. The port to OS/2 was done by Kai Uwe
+Rommel, with contributions and help from Darrel Hankerson.
+Andreas Buening now maintains the OS/2 port. The late Fred
+Fish supplied support for the Amiga, and Martin Brown
+provided the BeOS port. Stephen Davies provided the original
+Tandem port, and Matthew Woehlke provided changes for
+Tandem&rsquo;s POSIX-compliant systems. Dave Pitts provided
+the port to z/OS.</p>
+
+<p style="margin-left:11%; margin-top: 1em">See the
+<i>README</i> file in the <i>gawk</i> distribution for
+up-to-date information about maintainers and which ports are
+currently supported.</p>
+
+<h2>BUG REPORTS
+<a name="BUG REPORTS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">If you find a
+bug in <i>gawk</i>, please send electronic mail to
+<b>bug-gawk@gnu.org</b>. Please include your operating
+system and its revision, the version of <i>gawk</i> (from
+<b>gawk &minus;&minus;version</b>), which C compiler you
+used to compile it, and a test program and data that are as
+small as possible for reproducing the problem.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Before sending
+a bug report, please do the following things. First, verify
+that you have the latest version of <i>gawk</i>. Many bugs
+(usually subtle ones) are fixed at each release, and if
+yours is out of date, the problem may already have been
+solved. Second, please see if setting the environment
+variable <b>LC_ALL</b> to <b>LC_ALL=C</b> causes things to
+behave as you expect. If so, it&rsquo;s a locale issue, and
+may or may not really be a bug. Finally, please read this
+man page and the reference manual carefully to be sure that
+what you think is a bug really is, instead of just a quirk
+in the language.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Whatever you
+do, do <b>NOT</b> post a bug report in <b>comp.lang.awk</b>.
+While the <i>gawk</i> developers occasionally read this
+newsgroup, posting bug reports there is an unreliable way to
+report bugs. Instead, please use the electronic mail
+addresses given above.</p>
+
+<p style="margin-left:11%; margin-top: 1em">If you&rsquo;re
+using a GNU/Linux or BSD-based system, you may wish to
+submit a bug report to the vendor of your distribution.
+That&rsquo;s fine, but please send a copy to the official
+email address as well, since there&rsquo;s no guarantee that
+the bug report will be forwarded to the <i>gawk</i>
+maintainer.</p>
+
+<h2>BUGS
+<a name="BUGS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">The
+<b>&minus;F</b> option is not necessary given the command
+line variable assignment feature; it remains only for
+backwards compatibility.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Syntactically
+invalid single character programs tend to overflow the parse
+stack, generating a rather unhelpful message. Such programs
+are surprisingly difficult to diagnose in the completely
+general case, and the effort to do so really is not worth
+it.</p>
+
+<h2>SEE ALSO
+<a name="SEE ALSO"></a>
+</h2>
+
+
+
+<p style="margin-left:11%; margin-top: 1em"><i>egrep</i>(1),
+<i>getpid</i>(2), <i>getppid</i>(2), <i>getpgrp</i>(2),
+<i>getuid</i>(2), <i>geteuid</i>(2), <i>getgid</i>(2),
+<i>getegid</i>(2), <i>getgroups</i>(2), <i>usleep</i>(3)</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>The AWK
+Programming Language</i>, Alfred V. Aho, Brian W. Kernighan,
+Peter J. Weinberger, Addison-Wesley, 1988. ISBN
+0-201-07981-X.</p>
+
+<p style="margin-left:11%; margin-top: 1em"><i>GAWK:
+Effective AWK Programming</i>, Edition 4.0, shipped with the
+<i>gawk</i> source. The current version of this document is
+available online at
+<b>http://www.gnu.org/software/gawk/manual</b>.</p>
+
+<h2>EXAMPLES
+<a name="EXAMPLES"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">Print and sort
+the login names of all users:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="7%">
+</td>
+<td width="8%">
+
+
+<p><b>BEGIN</b></p></td>
+<td width="8%"></td>
+<td width="69%">
+
+
+<p><b>{ FS = &quot;:&quot; }</b></p></td></tr>
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="7%">
+</td>
+<td width="8%">
+</td>
+<td width="8%">
+
+
+<p><b>{ print $1 | &quot;sort&quot; }</b></p></td>
+<td width="69%">
+</td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Count lines in
+a file:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="7%">
+</td>
+<td width="8%">
+</td>
+<td width="77%">
+
+
+<p><b>{ nlines++ }</b></p></td></tr>
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="7%">
+</td>
+<td width="8%">
+
+
+<p><b>END</b></p></td>
+<td width="77%">
+
+
+<p><b>{ print nlines }</b></p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Precede each
+line by its number in the file:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>{ print FNR, $0 }</b></p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Concatenate and
+line number (a variation on a theme):</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>{ print NR, $0 }</b></p></td></tr>
+</table>
+
+<p style="margin-left:11%; margin-top: 1em">Run an external
+command for particular lines of data:</p>
+
+<table width="100%" border="0" rules="none" frame="void"
+       cellspacing="0" cellpadding="0">
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>tail &minus;f access_log |</b></p></td></tr>
+<tr valign="top" align="left">
+<td width="8%"></td>
+<td width="92%">
+
+
+<p><b>awk &rsquo;/myhome.html/ { system(&quot;nmap &quot;
+$1 &quot;&gt;&gt; logdir/myhome.html&quot;) }&rsquo;</b></p></td></tr>
+</table>
+
+<h2>ACKNOWLEDGEMENTS
+<a name="ACKNOWLEDGEMENTS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">Brian Kernighan
+of Bell Laboratories provided valuable assistance during
+testing and debugging. We thank him.</p>
+
+<h2>COPYING PERMISSIONS
+<a name="COPYING PERMISSIONS"></a>
+</h2>
+
+
+<p style="margin-left:11%; margin-top: 1em">Copyright
+&copy; 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+1999, 2001, 2002, 2003, 2004, 2005, 2007, 2009, 2010, 2011
+Free Software Foundation, Inc.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Permission is
+granted to make and distribute verbatim copies of this
+manual page provided the copyright notice and this
+permission notice are preserved on all copies.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Permission is
+granted to copy and distribute modified versions of this
+manual page under the conditions for verbatim copying,
+provided that the entire resulting derived work is
+distributed under the terms of a permission notice identical
+to this one.</p>
+
+<p style="margin-left:11%; margin-top: 1em">Permission is
+granted to copy and distribute translations of this manual
+page into another language, under the above conditions for
+modified versions, except that this permission notice may be
+stated in a translation approved by the Foundation.</p>
+<hr>
+</body>
+</html>