Listing 1: The prune script

#! /bin/bash
# script  to add in erasing ~ files, convert and zipping
# $Id: prune,v 1.3 1995/07/13 13:28:23 leisner Exp leisner $

# exit immediately on errors??
set -e

function echo
{
builtin echo -e "$*"
}

function usage {
echo  $progname [ -b9Zvq ] pathname [ pathname ... ]
echo  "\t-b -- leave ~ files along"
echo  "\t-9 -- use best zip level"
echo  "\t-Z -- use znew on .Z files"
echo  "\t-v -- be verbose"
echo  "\t-z -- zip uncompressed files"
echo  "\t-f -- follow symbolic links."
echo  "\t-n -- pretend and list commands which will run"
echo  "\t-o -- overwrite"
echo  "\t-h -- generate this help screen"
exit 1

}

function xargs {
command xargs --no-run-if-empty  $*
}

progname=$0
# this will be echo to show commands
pretend=

# if true, don't erase ~ files
leave_backups=

#  pass this to  commands, -v or null
verbose=

# null or -9, pass this to gzip/znew
level9=

# if set, convert .Z files to .gz
dot_Z=

# if -follow, pass this to find.
follow=

# if -f, force compression (remove old file)
overwrite=

# if set, gzip uncompressed files.
gzip=

while getopts "bohfz9vZn" c; do
case $c in
b)	leave_backups=true ;;
v)	verbose=-v ;;
Z)	dot_Z=true ;;
9)	level9=-9  ;;
n)	pretend=echo ;;
f)	follow=-follow;;
z)	gzip=true;;
o)	overwrite=-f;;
\? | h)
usage
;;
esac
done

shift $[OPTIND-1]

if [ $# -ne 1 ]; then
usage
fi

if [ $dot_Z ]; then
find $* -name '*.Z' -type f $follow  | xargs \
$pretend znew $overwrite $level9 $verbose
fi

if [ ! $leave_backups ]; then
find . -name '*~' -type f $follow | xargs $pretend rm  $verbose
fi

# ignore any ~ files, only do files
if [ $gzip ]; then
find . -name '*[!.gz]' -name '*[!~]' -type f $follow | xargs \
$pretend gzip $level9 $overwrite$verbose
fi

# End of File