X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=extras%2Fvolume_id%2Fvol_id.c;h=b3f810fc9d3d6082af10e4ad8e1a132fcc44c617;hp=60428ab5821a4417c10a6dd8f7947699ad698b85;hb=f46a8a98a79afcbb9e9910d7d71c1f8ef4e6637f;hpb=01618658fd82dbc5e6315b639f00e87c6fee3c54

diff --git a/extras/volume_id/vol_id.c b/extras/volume_id/vol_id.c
index 60428ab58..b3f810fc9 100644
--- a/extras/volume_id/vol_id.c
+++ b/extras/volume_id/vol_id.c
@@ -134,7 +134,7 @@ int main(int argc, char *argv[])
 		{ "export", 0, NULL, 'x' },
 		{ "skip-raid", 0, NULL, 's' },
 		{ "probe-all", 0, NULL, 'a' },
-		{ "offset", 1, NULL, 'o' },
+		{ "offset", 2, NULL, 'o' },
 		{ "help", 0, NULL, 'h' },
 		{}
 	};
@@ -196,7 +196,8 @@ int main(int argc, char *argv[])
 			probe_all = 1;
 			break;
 		case 'o':
-			offset = strtoull(optarg, NULL, 0);
+			if (optarg[0] != '\0')
+				offset = strtoull(optarg, NULL, 0);
 			break;
 		case 'h':
 			printf("Usage: vol_id [options] <device>\n"