Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site iclbra.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!gamma!epsilon!zeta!sabre!bellcore!decvax!genrad!mit-eddie!think!harvard!seismo!mcvax!ukc!stc!iclbra!apm
From: apm@iclbra.UUCP (Andy Merritt)
Newsgroups: net.unix
Subject: Re: Comment lines in the Bourne shell
Message-ID: <158@iclbra.UUCP>
Date: Thu, 13-Jun-85 19:02:09 EDT
Article-I.D.: iclbra.158
Posted: Thu Jun 13 19:02:09 1985
Date-Received: Mon, 17-Jun-85 20:13:35 EDT
References: <1194@uwmacc.UUCP>
Distribution: net
Organization: I.C.L., Lovelace Road, Bracknell, Berkshire.
Lines: 29
Xpath: stc stc-a

> I've noticed that on my system (2.8BSD) the Bourne shell
> comment character doesn't do what I expected.  The shell
> still looks at some characters on the line, even though
> the line is commented out.  For example, the comment
> 
> : to use this file type <name> | lpr
> 
> produces a message referring to the pipe, even though the whole
> line is commented out.  What am I missing?
> 
> -- 
> 	Jeff Percival ...!uwvax!uwmacc!jwp

According to the SysV documentation I have, ':' is a special command for which
the manual says
:	no effect; the command does nothing. A zero exit code is returned.

This implies that the effect is not to ignore the rest of the line as you  
expected, but to take as arguments anything up to a normal terminator and
then do nothing with them. The | is met in this case, and nothing is in the
input for the lpr.

I guess this must be what is happening on the 2.8BSD system also.

		Andy
    /^^^\
   ( o o )
--w---U---w--	  UUCP: ...!ukc!stc!iclbra!apm
"Wot, no news?"   MAIL: Andrew Merritt, ICL, Lovelace Rd, Bracknell, Berkshire