Date: Mon, 11 Aug 1997 13:20:24 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: "Peter J. Farley III" <pjfarley AT dorsai DOT org>
cc: djgpp AT delorie DOT com
Subject: Re: Is this error due to make, bash, or me?
In-Reply-To: <33ee1ed7.8219700@news.dorsai.org>
Message-ID: <Pine.SUN.3.91.970811131919.7085E-100000@is>
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On Sun, 10 Aug 1997, Peter J. Farley III wrote:

> Curiouser and curiouser.  I have been experimenting, and the following
> works, while my original does not.  I changed the directory name, too,
> in case the name "test" might be mis-interpreted:
> 
> sh.exe/stest$ cat makefile
> echo    :
>         echo ${SHELL}
> recurs  :
>         make cshell SHELL=/bin/sh
> cshell  :
>         echo ${SHELL}
>         sh -c "if test -f makefile; then echo cshell; fi"

This is the expected behavior, although it might seem
counter-intuitive at first.  The Mother of All Your Problems is that
you use SHELL=/bin/sh incorrectly.  The DJGPP port of Make only sets
$SHELL to the actual pathname if you put the line SHELL=/bin/sh *in
the Makefile*, like so:

	SHELL=/bin/sh

	echo    :
		echo ${SHELL}
	recurs  :
		make cshell
	cshell  :
		echo ${SHELL}
		if test -f makefile ; then echo cshell ; fi

In this example, Make will set SHELL to h:/bin/sh.exe, and everything
will work.

However, in your original Makefile you set SHELL on the sub-make
command-line, which is entirely different.  From the file README.dos
in the Make distribution:

      Note that the above special handling of "SHELL=" only happens
      for Makefiles; if you set $SHELL in the environment or on the
      Make command line, you are expected to give the complete
      pathname of the shell, including the filename extension.

Note the last part: ``including the filename extension''.  You need to
say "make cshell SHELL=/bin/sh.exe", then it would have worked.  The
crucial hint to the cause of your problem is that "echo ${SHELL}"
prints "/bin/sh" instead of "/bin/sh.exe".  When Make tries to invoke
that program, it fails because there's no file "/bin/sh"; hence you
get "Error -1".

The reason why "sh -c" miraculously makes this work is obvious: Make
searches along the PATH for the programs it invokes, whereas it
doesn't do so for the value of $SHELL, which is supposed to be a fully
qualified pathname, including the extension.