nonsense words for files

w. mansfield wfmans at ihuxb.UUCP
Tue May 21 08:05:42 AEST 1985


> > > On what UNIX systems (or what shells) is test part of the shell?  On
> > > every system (and shell) I've used, it's in /bin/test.
> 
> > 	/bin/test will probably always be there but in the SysV R2 Bourne
> > 	shell 'test' is a builtin.
> 
> It's a builtin in System III and System V (release 1 and 2).  It probably
> was a builtin in UNIX/TS 1.0 and PWB/UNIX 2.0 (the predecessors to System
> III).  System V doesn't have "/bin/test" because it doesn't need it.  There
> is also a stub of code in the V7 shell (which is the 4.xBSD shell as well)
> to have "test" be a builtin under the name "[".  In the TS 1.0/PWB 2.0/S3/S5
> shell, it's builtin under the name "[" as well as "test".  Furthermore, if
> you do
> 
> 	ln /bin/test /bin/[
> 
> under V7, you can call it "[" as well; 4.xBSD comes with this already done.
> That way, you can write
> 
> 	if [ -f /etc/foo ]
> 
> instead of
> 
> 	if test -f /etc/foo
> 
> which, arguably, looks cleaner.
> 
> Building it into the shell makes scripts which do lots of "test"s run much
> faster.
> 
> 	Guy Harris

AIIIIIIEEEEE!  I'm sorry I started a UNIX dialogue in net.nlang.
If there's interest, let's move the discussion to net.unix only,
and leave the language au natural folks alone.
-- 

	Bill Mansfield
	AT&T Information Systems, Naperville, IL
	{ihnp4!}ihuxb!wfmans



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