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From: hahn@nas.nasa.gov (Jonathan Hahn)
Newsgroups: comp.unix.internals
Subject: Re: puzzle
Message-ID: <1990Nov27.024517.2207@nas.nasa.gov>
Date: 27 Nov 90 02:45:17 GMT
References: <1990Nov27.003659.3521@informix.com>
Sender: news@nas.nasa.gov
Distribution: usa
Organization: NAS Program, NASA Ames Research Center, Moffett Field, CA
Lines: 29

In article <1990Nov27.003659.3521@informix.com> housed@infmx.informix.com (Darryl House) writes:
>The following is a Bourne shell script that illustrates
>what I am trying to do: set a shell variable that
>contains the contents of another one that is referred
>to by concatenating two others. Sufficiently confusing?

The following script creates a string which accomplishes the
assignment to ITERATION, and calls "eval" to evaluate the string.
BTW, the echo needs double quotes so the value of ITERATION will
be printed.

----------------------------------------------------------------------
	firsttime="first_time"
	secondtime="second_time"

	PREFIX_WORDS="first second"
	SUFFIX="time"

	for PREFIX in $PREFIX_WORDS
	do
	    eval 'ITERATION=$'$PREFIX$SUFFIX
	    echo "Iteration is $ITERATION"
	done
----------------------------------------------------------------------

-jonathan hahn
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