Bruce Korb wrote:
> On 01/03/11 16:13, Eric Blake wrote:
>> $ /bin/sh -c 'v=`nonesuch` 2>/dev/null'
>> nonesuch: not found
>> $ /bin/sh -c 'v=`(nonesuch) 2>/dev/null`'
>> $
>
> Just for grins, how about trying:
>
> /bin/sh -c 'v=`exec 2>/dev/null;nonesuch`'
>
> I think it works for me on a Sun box:
>
> sunfall_bkorb $ /bin/sh -c '`nonesuch`' 2>/dev/null
> sunfall_bkorb $ /bin/sh -c '`nonesuch` 2>/dev/null'
> /bin/sh: nonesuch: not found
> sunfall_bkorb $ /bin/sh -c '`exec 2>/dev/null;nonesuch`'
Good idea. Avoiding an unnecessary sub-shell is always welcome.
I'll wait for your "ok".
>From fa6be5b2b297b569d890535b0126054789f8a6fb Mon Sep 17 00:00:00 2001
From: Bruce Korb <bk...@gnu.org>
Date: Tue, 4 Jan 2011 09:47:49 +0100
Subject: [PATCH] git-version-gen: avoid a sub-shell
* build-aux/git-version-gen: Redirect stderr in `...` via
"exec 2>...", rather than via an added sub-shell.
---
ChangeLog | 6 ++++++
build-aux/git-version-gen | 4 ++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index bb3d9cf..b8456de 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2011-01-04 Bruce Korb <bk...@gnu.org>
+
+ git-version-gen: avoid a sub-shell
+ * build-aux/git-version-gen: Redirect stderr in `...` via
+ "exec 2>...", rather than via an added sub-shell.
+
2011-01-03 Ben Pfaff <b...@cs.stanford.edu>
git-version-gen: use (...) rather than sh -c '...'
diff --git a/build-aux/git-version-gen b/build-aux/git-version-gen
index 694ba46..6f8b160 100755
--- a/build-aux/git-version-gen
+++ b/build-aux/git-version-gen
@@ -1,6 +1,6 @@
#!/bin/sh
# Print a version string.
-scriptversion=2011-01-03.20; # UTC
+scriptversion=2011-01-04.08; # UTC
# Copyright (C) 2007-2011 Free Software Foundation, Inc.
#
@@ -143,7 +143,7 @@ v=`echo "$v" |sed 's/^v//'`
# Don't declare a version "dirty" merely because a time stamp has changed.
git update-index --refresh > /dev/null 2>&1
-dirty=`(git diff-index --name-only HEAD) 2>/dev/null` || dirty=
+dirty=`exec 2>/dev/null; git diff-index --name-only HEAD` || dirty=
case "$dirty" in
'') ;;
*) # Append the suffix only if there isn't one already.
--
1.7.3.4
