Btrfs-progs, btrfs-map-logical: Fix typo in usage

The right option is 'o' not 'c'. And this tool is used for the block devices
on which there is a btrfs file system, so change "mount_point" to "device".

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>

diff --git a/btrfs-map-logical.c b/btrfs-map-logical.c
index d79a73a..fa4fb3f 100644 (file)
--- a/btrfs-map-logical.c
+++ b/btrfs-map-logical.c
@@ -84,7 +84,7 @@ struct extent_buffer *debug_read_block(struct btrfs_root *root, u64 bytenr,
 
 static void print_usage(void)
 {
-       fprintf(stderr, "usage: btrfs-map-logical [options] mount_point\n");
+       fprintf(stderr, "usage: btrfs-map-logical [options] device\n");
        fprintf(stderr, "\t-l Logical extent to map\n");
        fprintf(stderr, "\t-c Copy of the extent to read (usually 1 or 2)\n");
        fprintf(stderr, "\t-o Output file to hold the extent\n");
@@ -96,7 +96,7 @@ static struct option long_options[] = {
        /* { "byte-count", 1, NULL, 'b' }, */
        { "logical", 1, NULL, 'l' },
        { "copy", 1, NULL, 'c' },
-       { "output", 1, NULL, 'c' },
+       { "output", 1, NULL, 'o' },
        { "bytes", 1, NULL, 'b' },
        { 0, 0, 0, 0}
 };