shortlog: support outputting to streams other than stdout

This will be needed to avoid freopen() in `git format-patch`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/shortlog.h b/shortlog.h
index de4f86fb97..5a326c6860 100644
--- a/shortlog.h
+++ b/shortlog.h
@@ -17,6 +17,7 @@ struct shortlog {
 	char *common_repo_prefix;
 	int email;
 	struct string_list mailmap;
+	FILE *file;
 };
 
 void shortlog_init(struct shortlog *log);