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SHELL-QUOTE(1)		       User Contributed Perl Documentation		   SHELL-QUOTE(1)

       shell-quote - quote arguments for safe use, unmodified in a shell command

       shell-quote [switch]... arg...

       shell-quote lets you pass arbitrary strings through the shell so that they won't be
       changed by the shell.  This lets you process commands or files with embedded white space
       or shell globbing characters safely.  Here are a few examples.

       ssh preserving args
	   When running a remote command with ssh, ssh doesn't preserve the separate arguments it
	   receives.  It just joins them with spaces and passes them to "$SHELL -c".  This
	   doesn't work as intended:

	       ssh host touch 'hi there'	   # fails

	   It creates 2 files, hi and there.  Instead, do this:

	       cmd=`shell-quote touch 'hi there'`
	       ssh host "$cmd"

	   This gives you just 1 file, hi there.

       process find output
	   It's not ordinarily possible to process an arbitrary list of files output by find with
	   a shell script.  Anything you put in $IFS to split up the output could legitimately be
	   in a file's name.  Here's how you can do it using shell-quote:

	       eval set -- `find -type f -print0 | xargs -0 shell-quote --`

       debug shell scripts
	   shell-quote is better than echo for debugging shell scripts.

	       debug() {
		   [ -z "$debug" ] || shell-quote "debug:" "$@"

	   With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar",
	   but with shell-quote you can.

       save a command for later
	   shell-quote can be used to build up a shell command to run later.  Say you want the
	   user to be able to give you switches for a command you're going to run.  If you don't
	   want the switches to be re-evaluated by the shell (which is usually a good idea, else
	   there are things the user can't pass through), you can do something like this:

	       while [ $# != 0 ]
		   case x$1 in
			   [ $# -gt 1 ] || die "need an argument for $1"
			   user_switches="$user_switches "`shell-quote -- "$2"`
		       # process other switches
	       # later
	       eval "shell-quote some-command $user_switches my args"

	   Turn debugging on.

	   Show the usage message and die.

	   Show the version number and exit.

       The code is licensed under the GNU GPL.	Check http://www.argon.org/~roderick/ or CPAN for
       updated versions.

       Roderick Schertler <roderick@argon.org>

perl v5.16.3				    2010-06-11				   SHELL-QUOTE(1)
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