qemu-img: show help for invalid global options
The qemu-img sub-command executes regardless of invalid global options:
$ qemu-img --foo info test.img
qemu-img: unrecognized option '--foo'
image: test.img
...
The unrecognized option warning may be missed by the user. This can
hide incorrect command-lines in scripts and confuse users.
This patch prints the help information and terminates instead of
executing the sub-command.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id:
20170317104541.28979-2-stefanha@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>