Re: [PATCH v2 1/2] storage-daemon: report unexpected arguments on the fly

[Paolo Bonzini]

On 01/03/21 16:38, Eric Blake wrote:
> On 3/1/21 9:28 AM, Paolo Bonzini wrote:
> > If the first character of optstring is '-', then each nonoption argv
> > element is handled as if it were the argument of an option with character
> > code 1.  This removes the reordering of the argv array, and enables usage
> > of loc_set_cmdline to provide better error messages.
> >
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > ---
> >   storage-daemon/qemu-storage-daemon.c | 9 ++++-----
> >   1 file changed, 4 insertions(+), 5 deletions(-)
>
> Nice.  The man page for 'getopt_long' is unclear whether setting
> POSIXLY_CORRECT in the environment would break this

It doesn't.  In fact, with this patch the behavior is the same as for 
POSIXLY_CORRECT, though for unrelated reasons, and interestingly enough 
I think the POSIXLY_CORRECT behavior is an improvement for 
qemu-storage-daemon.

Unpatched:

$ qemu-storage-daemon foo --object iothread
qemu-storage-daemon: Parameter 'id' is missing

$ POSIXLY_CORRECT=1 qemu-storage-daemon foo --object iothread
qemu-storage-daemon: Unexpected argument: foo

Patched:

$ storage-daemon/qemu-storage-daemon foo --object iothread
qemu-storage-daemon: foo: Unexpected argument
$ POSIXLY_CORRECT=1 storage-daemon/qemu-storage-daemon foo --object iothread
qemu-storage-daemon: foo: Unexpected argument

Paolo