btrfs-progs: use usage() to replace the warning msg on no-arg usage

To be consistent with the other cmds, replace the warning msg
with usage() when send/receive are used without any args.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 2 insertions, 4 deletions

diff --git a/cmds-receive.c b/cmds-receive.c
index 2d55c539..d6cd3da4 100644
--- a/cmds-receive.c
+++ b/cmds-receive.c
@@ -951,10 +951,8 @@ int cmd_receive(int argc, char **argv)
 		}
 	}
 
-	if (optind + 1 != argc) {
-		fprintf(stderr, "ERROR: receive needs path to subvolume\n");
-		return 1;
-	}
+	if (check_argc_exact(argc - optind, 1))
+		usage(cmd_receive_usage);
 
 	tomnt = argv[optind];