From e5d9109aabc163148fe4cf07f9d36aff9b067fb6 Mon Sep 17 00:00:00 2001
From: Eitan Adler <eadler@FreeBSD.org>
Date: Wed, 30 May 2012 04:06:38 +0000
Subject: [PATCH] Only set _w to 0 when the file stream is not currently
 reading. Without this fflush may fail to write data in the buffer.

PR:		kern/137819
Submitted by:	Eric Blake <ebb9@byu.net>
Reviewed by:	theraven
Approved by:	cperciva
MFC after:	2 weeks
---
 lib/libc/stdio/fpurge.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/libc/stdio/fpurge.c b/lib/libc/stdio/fpurge.c
index 6a2c70c3c5da..148e490eafe2 100644
--- a/lib/libc/stdio/fpurge.c
+++ b/lib/libc/stdio/fpurge.c
@@ -62,7 +62,7 @@ fpurge(fp)
 			FREEUB(fp);
 		fp->_p = fp->_bf._base;
 		fp->_r = 0;
-		fp->_w = fp->_flags & (__SLBF|__SNBF) ? 0 : fp->_bf._size;
+		fp->_w = fp->_flags & (__SLBF|__SNBF|__SRD) ? 0 : fp->_bf._size;
 		retval = 0;
 	}
 	FUNLOCKFILE(fp);