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From: carl@bdaemon.UUCP (carl)
Newsgroups: net.unix-wizards
Subject: Re: In sh, is '[' a portable synonym for 'test'?
Message-ID: <313@bdaemon.UUCP>
Date: Tue, 15-Oct-85 10:57:44 EDT
Article-I.D.: bdaemon.313
Posted: Tue Oct 15 10:57:44 1985
Date-Received: Sat, 19-Oct-85 03:54:28 EDT
References: <482@phri.UUCP> <2887@sun.uucp>
Distribution: net
Organization: Daemon Assoc., Boulder, CO
Lines: 21

> > 
> > 	On my 4.2bsd system, the following do the same thing in sh because
> > /bin/[ is a link to /bin/test. ... Is the "[]" form safe to use if you want
> > ....
> 
> V7 systems where /bin/[ isn't a link to /bin/test.  Any V7 or post-V7 system
> can be made to support "if [ <condition> ]" as equivalent to "if test
> .....
> 	GUy Harris

I have absolutely no arguments with Guy's message, but would like to point
out that the [ condition ] construct saves only one keystroke at the
expense of readability.  E.g.:

	if test -f "$1"	<= 15 keystrokes + <CR>
vs.
	if [ -f "$1" ]	<= 14 keystrokes + <CR>

Which is more readable? Note that the spaces around [] are MANDATORY.

Carl Brandauer