On 02/16/2012 03:59 AM, Jim Meyering wrote:
>> I think Davide's point is not about the # comment ... rm won't see
>> that on argv anyway. The point is that 'rm -f' does not complain about
>> missing operands while 'rm' does:
>>
>>   $ rm
>>   rm: missing operand
>>   Try `rm --help' for more information.
>>   $ rm -f
>>   $
>>
>> According to the info, '-f' just silences error messages for files
>> which do not exist (and never to prompt for confirmation), but why
>> should it also affect the "missing operand" message?
> 
> Two reasons:
> 
>  - that's what rm -f has always done
>  - because that's more useful.  Otherwise, "rm -rf $file_list" would
>    have to be wrapped in code to handle specially the case in which
>    $file_list is empty.

You can always use 'rm -rf dummy $file_list' without having to check for
whether $file_list is empty, but yes, that is the primary reasoning why
-f with no options behaves differently than any other case with no options.

FYI: I just opened a POSIX bug report, asking that this usage be
codified (since everyone that I tested already does it):
http://austingroupbugs.net/view.php?id=542

-- 
Eric Blake   eblake@redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org