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Re: problem
From: |
Paul D. Smith |
Subject: |
Re: problem |
Date: |
Thu, 19 Dec 2002 07:48:19 -0500 |
%% "Ashish Bajpai (DS/ESQ2)" <address@hidden> writes:
ab> Can someone tell me the meaning of automatic variable $$? which is
ab> used sometimes in makefile ?
This is not actually a question specific to the Windows port of GNU make
so might be better asked on address@hidden or similar.
ab> elif [ $$? -eq 2 ] ; then \
The construct "$$" escapes the dollar sign so that make won't think that
it introduces a make variable. So really this isn't a make question at
all, it's a shell question: when you see "$$?" in the command script it
gets passed to the shell as "$?".
The shell variable $? is always set to the exit code of the
just-completed command, so the above test is checking whether the
previous command exited with an error code of 2. In UNIX, all commands
that succeed exit with a result value of 0, and any non-0 value is
considered an error.
--
-------------------------------------------------------------------------------
Paul D. Smith <address@hidden> Find some GNU make tips at:
http://www.gnu.org http://make.paulandlesley.org
"Please remain calm...I may be mad, but I am a professional." --Mad Scientist
- problem, Ashish Bajpai (DS/ESQ2), 2002/12/19
- Re: problem,
Paul D. Smith <=