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Re: a small question about subst
From: |
John Graham-Cumming |
Subject: |
Re: a small question about subst |
Date: |
Thu, 12 May 2005 16:30:38 -0400 |
On Thu, 2005-05-12 at 16:18 -0400, Ken Smith wrote:
> Without seeing your code, I can only assume that you are trying to do
> this in the command section of a rule. If that is the case, you'll need
> to use sed or something similar. The GNU make functions will be
> processed when the files are read and not when the targets are run. At
> that time, $< has no value and your statements evaluate to the empty
> string.
Sorry, that's totally wrong.
The commands within a rule are not expanded/substituted until they are
needed (i.e. just before the rule's commands are about to be executed)
and hence $< etc. are perfectly valid within a rule. There's no need to
use sed.
John.
--
John Graham-Cumming
Home: http://www.jgc.org/
Work: http://www.electric-cloud.com/
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