[libvirt] [PATCH] build: silence configure warning if ksh is missing

[Eric Blake]

* configure.ac (lv_cv_wrapper_shell): Fix logic error if candidate
shell is not available.
Reported by Matthias Bolte.
---

On IRC, Matthias reported a noisy configure run:

eblake: checking for shell that supports <> redirection... ./configure: line 31581: ksh: command not found

Worse, if a shell is missing, it doesn't change the contents of
conftest.a, so that missing shell would be selected in the loop.
This patch fixes both the noise and the wrong selection.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/configure.ac b/configure.ac
index 86a864b..7e7f295 100644
--- a/configure.ac
+++ b/configure.ac
@@ -616,7 +616,7 @@ if test "$with_qemu" = yes; then
         test $lv_cv_wrapper_shell = none &&
           AC_MSG_ERROR([could not find decent shell])
         echo a > conftest.a
-        $lv_cv_wrapper_shell -c ': 1<>conftest.a'
+        ($lv_cv_wrapper_shell -c ': 1<>conftest.a') 2>/dev/null &&
         case `cat conftest.a`.$lv_cv_wrapper_shell in
           a./*) break;; dnl /bin/sh is good enough
           a.*) dnl bash, ksh, and zsh all understand 'command', use that
-- 
1.7.2.3