From c0751d323e96fcaaecba289b71970388972ee608 Mon Sep 17 00:00:00 2001
From: Simon Riggs <simon@2ndQuadrant.com>
Date: Tue, 7 Aug 2012 16:22:58 +0100
Subject: [PATCH] fsync backup_label after pg_start_backup()

Dave Kerr, backpatched by Simon Riggs
---
 src/backend/access/transam/xlog.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 0cab155fcf..9a9b04f242 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -8546,7 +8546,7 @@ pg_start_backup(PG_FUNCTION_ARGS)
 				checkpointloc.xlogid, checkpointloc.xrecoff);
 		fprintf(fp, "START TIME: %s\n", strfbuf);
 		fprintf(fp, "LABEL: %s\n", backupidstr);
-		if (fflush(fp) || ferror(fp) || FreeFile(fp))
+		if (fflush(fp) || ferror(fp) || pg_fsync(fileno(fp)) != 0 || FreeFile(fp))
 			ereport(ERROR,
 					(errcode_for_file_access(),
 					 errmsg("could not write file \"%s\": %m",