Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!water!watmath!clyde!rutgers!labrea!decwrl!sun!guy
From: guy@sun.UUCP
Newsgroups: comp.unix.questions
Subject: Re: An awk question or two...
Message-ID: <27817@sun.uucp>
Date: Sat, 12-Sep-87 02:14:57 EDT
Article-I.D.: sun.27817
Posted: Sat Sep 12 02:14:57 1987
Date-Received: Sun, 13-Sep-87 08:16:22 EDT
References: <3931@well.UUCP>
Distribution: na
Organization: Sun Microsystems, Inc. - Mtn View, CA
Lines: 33
Keywords: awk ranges

> 	awk -f comline.awk comvar=\"SUB\" ascii.h
> 
> 	this is the file comline.awk:
> 	
> 	comvar	{ print }
> 
> 	and, the result:
> 
> 323 bin/src :-} !aw
> awk -f comline.awk comvar=\"SUB\" ascii.h
> awk: syntax error near line 1
> awk: bailing out near line 1
> 324 bin/src :-}

"comvar" is not a legal pattern.  A pattern is either a keyword (such as BEGIN
or END), a relational expression, or a regular expression.  You can't just
throw a variable name there and expect "awk" to treat that as a regular
expression that matches all lines that contain that regular expression; "awk"
doesn't permit that.

What you want to do instead is to pass the program to "awk" *on the command
line*, and put it in double quotes so that shell variables are expanded before
the string is passed to "awk".  E.g., in a shell script, you could have the
command:

	awk "/$1/ { print }" ...

which would tell "awk" to print whatever lines were matched by the pattern
specified by the first argument to that shell script.
-- 
	Guy Harris
	{ihnp4, decvax, seismo, decwrl, ...}!sun!guy
	guy@sun.com (or guy@sun.arpa)