run-with-agent

#!/bin/bash

PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin

progname=$(basename $0)
socket=/var/run/$(whoami)/ssh-agent.sock

usage() {
  echo "usage: $progname [-s socket] command"
  echo ""
  echo "s socket   the full path to the agent socket"
}

while getopts hs: opt; do
  case $opt in
    h)
      usage
      exit 0
      ;;
    s)
      socket=$OPTARG
      ;;
    *)
      usage
      exit 1
      ;;
  esac
done
shift $((OPTIND-1))

command="$@"
if [[ -z $command ]]; then
  echo "$progname: command is required" >&2
  exit 1
fi

export SSH_AUTH_SOCK=$socket

ssh-add -l >/dev/null 2>&1
agent_rc=$?

case $agent_rc in
0)
  exec $command
  ;;
1)
  echo "$progname: ssh-agent is running but no keys are loaded" >&2
  exit 2
  ;;
2)
  echo "$progname: ssh-agent isn't running" >&2
  exit 3
  ;;
esac