@@ -103,7 +103,12 @@ static void help(void)
" '-a' applies a snapshot (revert disk to saved state)\n"
" '-c' creates a snapshot\n"
" '-d' deletes a snapshot\n"
- " '-l' lists all snapshots in the given image\n";
+ " '-l' lists all snapshots in the given image\n"
+ "\n"
+ "Parameters to compare subcommand:\n"
+ " '-f' first image format\n"
+ " '-F' second image format\n"
+ " '-s' run in Strict mode - fail on different image size or sector allocation\n";
printf("%s\nSupported formats:", help_msg);
bdrv_iterate_format(format_print, NULL);
@@ -84,6 +84,18 @@ deletes a snapshot
lists all snapshots in the given image
@end table
+Parameters to compare subcommand:
+
+@table @option
+
+@item -f
+First image format
+@item -F
+Second image format
+@item -s
+Strict mode - fail on on different image size or sector allocation
+@end table
+
Command description:
@table @option
@@ -117,6 +129,26 @@ it doesn't need to be specified separately in this case.
Commit the changes recorded in @var{filename} in its base image.
+@item compare [-f @var{fmt}] [-F @var{fmt}] [-p] [-s] [-q] @var{filename1} @var{filename2}
+
+Check if two images have the same content. You can compare images with
+different format or settings.
+
+The format is probed unless you specify it by @var{-f} (used for @var{filename1}) and/or @var{-F} (used for @var{filename2}) option.
+
+By default, images with different size are considered identical if the larger
+image contains only unallocated and/or zeroed sectors in the area after the end
+of the other image. In addition, if any sector is not allocated in one image
+and contains only zero bytes in the second one, it is evaluated as equal. You
+can use Strict mode by specifying the @var{-s} option. When compare runs in
+Strict mode, it fails in case image size differs or a sector is allocated in
+one image and is not allocated in the second one.
+
+By default, compare prints out a result message. This message displays
+information that both images are same or the position of the first different
+byte. In addition, result message can report different image size in case
+Strict mode is used.
+
@item convert [-c] [-p] [-f @var{fmt}] [-t @var{cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename}
Convert the disk image @var{filename} or a snapshot @var{snapshot_name} to disk image @var{output_filename}
Adding documentation for new qemu-img subcommand compare. Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com> --- qemu-img.c | 7 ++++++- qemu-img.texi | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+), 1 deletions(-)