Re: [Fwd: isatty function?]

[Paul D. Smith]

%% mst <address@hidden> writes:

  m> How about a way to call "system" without catching stdout, let
  m> stdout be copied as is to the child process?

  >> Hmm.  Maybe.  I still don't know that it's that useful.

  m> I know I wanted to get the exit status of the program into a
  m> variable many times.  This would be possible:

While not saying I think a $(system ...) function is not useful (I still
have this under advisement), I will say that the examples you give are
already fairly easily done:

  m> ifeq ($(system test -e filename),0)
  m> --FILE exists
  m> else
  m> --FILE does not exist
  m> endif

This is much more efficiently done with the $(wildcard) function:

 ifneq ($(wildcard filename),)
 --FILE exists
 else
 --FILE does not exist
 endif

Avoids a shell invocation, test invocation, etc.

  m> Another example: print date to stdout while makefile is evaluated:

  m> dummy:=$(shell date)

Yes; you can do this but it's a big more ugly:

  dummy := $(shell date 1>&2)

also the result goes to STDERR instead of STDOUT, which might not be
what you wanted.

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