From: Robin H. Johnson <robbat2@gentoo.org>
Date: Tue, 04 Jan 2011 20:35:38 GMT
Subject: Re: [PATCH v2] Fix false positives in t3404 due to SHELL=/bin/false
Message-ID: <robbat2-20110104T203312-513011947Z@orbis-terrarum.net>
In-Reply-To: <982E526FA742C94E9AC26DA766FD07090A3399@NYCMBX3.winmail.deshaw.com>

On Tue, Jan 04, 2011 at 09:43:12AM -0500, Vallon, Justin wrote:
>  # "exec" commands are ran with the user shell by default, but this may
>  # be non-POSIX. For example, if SHELL=zsh then ">file" doesn't work
>  # to create a file. Unseting SHELL avoids such non-portable behavior
> 
> Perl's exec and system do not use SHELL (as far as perlfunc states).  It uses
> /bin/sh -c "$cmd", or a platform-dependent equivalent.
> 
> $SHELL is typically only used when a program wants to invoke a user-shell
> (ie: editor shell-escape, xterm, typescript, screen).
> 
> How was SHELL=/bin/false causing problems?  Is git using $SHELL?
git-rebase--interactive.sh:
====
${SHELL:-@SHELL_PATH@} -c "$rest" # Actual execution
status=$?
if test "$status" -ne 0
then
	warn "Execution failed: $rest"
====

This always triggers with SHELL=/bin/false if SHELL is unset or empty,
SHELL_PATH gets substituted, which tends to be the correct /bin/sh.

-- 
Robin Hugh Johnson
Gentoo Linux: Developer, Trustee & Infrastructure Lead
E-Mail     : robbat2@gentoo.org
GnuPG FP   : 11AC BA4F 4778 E3F6 E4ED  F38E B27B 944E 3488 4E85