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From: maart@cs.vu.nl (Maarten Litmaath)
Newsgroups: comp.unix.questions
Subject: Re: csh question -- aliasing, quoting and the like
Keywords: csh alias quotes
Message-ID: <3303@solo9.cs.vu.nl>
Date: 20 Sep 89 03:41:03 GMT
References: <498@westc.UUCP>
Organization: V.U. Informatica, Amsterdam, the Netherlands
Lines: 48

gjoost@westc.UUCP (Gertjan van Oosten) writes:
\...
\% alias killroy 'kill `ps ax | grep -w roy | grep -v grep | awk '{print $1}'`'

The `string' is broken into words as follows:

	'kill `ps ax | grep -w roy | grep -v grep | awk '{print

	$1}'`'

i.e. parts of the string aren't quoted.
Solution:

	'kill ... awk '\''{print $1}'\''`'
	^             ^  ^          ^  ^ ^
	+-------------+  +----------+  +-+

\...
\% alias killroy 'rsh host kill `ps ax | grep -w roy | grep -v grep |
\                                awk '{print $1}'`'

This would become:

	alias	killroy \
	'rsh host kill '\''`ps ... awk '\'\\\'\''{print $1}'\'\\\'\''`'\'

Er, say that again?
Of course this isn't the optimal solution, regarding the number of quotes and
backslashes; it is, however, a GENERAL solution.
The following trick might be helpful:

	set	q	= \'
	set	b	= \\
	set	q1	= $b$q
	set	b1	= $b$b
	set	q2	= $b1$q1
	# etc.

	alias	killroy \
	'rsh host kill '$q'`ps ... awk '$q$q1$q'{print $1}'$q$q1$q'`'$q
	                 ^               ^    ^             ^    ^    ^
	                 +---------------+    +-------------+    +----+

i.e. $q is a real quote, $q1 will be a real quote one interpretation level
deeper and so on.
-- 
   creat(2) shouldn't have been create(2): |Maarten Litmaath @ VU Amsterdam:
      it shouldn't have existed at all.    |maart@cs.vu.nl, mcvax!botter!maart