✏ EDIT: espdiff

#!/bin/bash
#
# espdiff - do whatever it was you wanted
# Copyright (C) 2003 Tim Waugh <twaugh@redhat.com>

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

version() {
  echo "espdiff - patchutils version 0.3.4"
}

usage() {
  echo "usage: espdiff [OPTION...] [FILE...]"
}

deep_brainwave=0
recurse=0
compare=0
while [ "$#" -gt 0 ]
do
  case "$1" in
  --help)
	usage
	exit 0
	;;
  --version)
	version
	exit 0
	;;
  --deep-brainwave-mode)
	deep_brainwave=1
	shift
	;;
  --recurse)
	recurse=1
	shift
	;;
  --compare)
	compare=1
	shift
	;;
  --)
	shift
	break
	;;

*)
	break
	;;
  esac
done

for each in "$@"
do
  error=$(cat "$each" 2>&1 >/dev/null)
  if [ $? -ne 0 ]
  then
    echo >&2 "espdiff${error#cat}"
    exit 1
  fi
done

delay=3
if [ "$deep_brainwave" -ne 0 ]
then
  delay=$(($delay * 2))
fi

read -t $delay -p 'Please concentrate... ' || echo
echo 'No brainwave activity detected.  Aborting.'
exit 1

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