From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 15 Dec 2008 08:33:34 +0000 (-0800)
Subject: pager: do not dup2 stderr if it is already redirected
X-Git-Tag: v1.6.0.6~8
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/a8335024c294db470e16e9df3aaa346bfcfbeacb

pager: do not dup2 stderr if it is already redirected

An earlier commit 61b8050 (sending errors to stdout under $PAGER,
2008-02-16) avoided losing the error messages that are sent to the
standard error when $PAGER is in effect by dup2'ing fd 2 to the pager.
his way, showing a tag object that points to a bad object:

$ git show tag-foo

would give the error message to the pager.  However, it was not quite
right if the user did:

$ git show 2>error.log tag-foo

i.e. use the pager but store the errors in a separate file.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/pager.c b/pager.c
index 6b5c9e44b4..0b7e55f476 100644
--- a/pager.c
+++ b/pager.c
@@ -102,7 +102,8 @@ void setup_pager(void)
 
 	/* original process continues, but writes to the pipe */
 	dup2(pager_process.in, 1);
-	dup2(pager_process.in, 2);
+	if (isatty(2))
+		dup2(pager_process.in, 2);
 	close(pager_process.in);
 
 	/* this makes sure that the parent terminates after the pager */