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From: jar@ZURICH.AI.MIT.EDU (Jonathan Rees)
Newsgroups: gnu.utils.bug
Subject: make compatibility problem: $(shell ...) vs. `...`
Message-ID: <9002132348.AA15570@zurich.ai.mit.edu>
Date: 13 Feb 90 23:48:29 GMT
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Distribution: gnu
Organization: GNUs Not Usenet
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The "make" supplied by at least two different vendors (HP and Sun(?))
supports the following feature: I can write a variable assignment of
the form

	VAR = `a shell command`

(e.g., DIR = `pwd`) and get behavior analgous to that of csh.  In GNU
make, I instead write

	VAR = $(shell a shell command)

Now I can easily believe that GNU make is doing "the right thing," but
my problem is that I can't think of anything I can write in a makefile
to get this effect, such that the makefile will work either with GNU
make or HP (etc.) make.  Isn't this contrary to the usual policy for
GNU utilities?  The GNU make manual explicitly mentions the
correspondence between $(shell ...) and `...`, so I assume you don't
consider the incompatibility a bug; but why isn't it, and do you have
any suggestions for a workaround?

Thanks, and keep up the good work,

Jonathan Rees