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README.md

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 # assemble_synApps
 synApps assemble script
+
+Used to pull a user-defined set of EPICS modules at given tags and package them into a
+single synApps directory that will build with a single 'make' command.
+
+## usage
+
+The script can be called by itself and will use a default set of modules and tags to
+build the synApps release. There are also a set of command line options to customize
+the setup as needed. Or otherwise, the script itself is rather easy to find and replace
+default values.
+
+### Command Line Interface
+
+The command line options that assemble_synApps recognizes are:
+
+* --config=
+* --dir=
+* --base=
+* --set ABC=123
+* --check
+* --help
+
+#### config
+
+The config option is used to provide a separate file with a list of modules and their tags.
+This file should be arranged with each definition on their own line and in the form of
+    MODULE_NAME=module_tag
+
+Module definitions are read in and used instead of the default values listed in the
+assemble_synApps script. This is a full replacement, not overwriting the values, so if a
+module isn't defined in the config file provided, it will not use any default value, said
+module just will not be downloaded.
+
+
+#### dir
+
+The dir option is used to define the name of the synApps directory to be created. All modules
+will be downloaded into the folder structure synApps_dir_name/support.
+
+
+#### base
+
+The base option is used to define the location of the installation of EPICS base on your system
+that synApps will link against.
+
+
+#### set
+
+The set option is used to make individual changes to the module definitions you will be using.
+Each usage of the `--set` option should be followed by a string in the form of
+    MODULE_NAME=module_tag
+
+These module definitions will either be created in the list of modules to download if they don't
+already exist, or will overwrite an existing definition. This works regardless of if one is
+using the default module definitions or if you have a config file.
+
+
+#### check
+
+The check option is a sanity check before you fully run the script. It will display the values of
+all the module definitions that it will be downloading.