Documentation/accounting/getdelays.c: handle sendto() failures

Fixes

  Documentation/accounting/getdelays.c: In function `get_family_id':
  Documentation/accounting/getdelays.c:172:14: warning: variable `rc' set but not used [-Wunused-but-set-variable]
Reported-by: N"Justin P. Mattock" <justinmattock@gmail.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/accounting/getdelays.c

@@ -177,6 +177,8 @@ static int get_family_id(int sd)
 	rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
 			CTRL_ATTR_FAMILY_NAME, (void *)name,
 			strlen(TASKSTATS_GENL_NAME)+1);
+	if (rc < 0)
+		return 0;	/* sendto() failure? */
 
 	rep_len = recv(sd, &ans, sizeof(ans), 0);
 	if (ans.n.nlmsg_type == NLMSG_ERROR ||