Re: [PATCH] git-new-workdir: Don't fail if the target directory is empty

From: Junio C Hamano <gitster@pobox.com>
Date: Nov 18, 2014, 19:32 UTC
Message-ID: <xmqq8uj8wbhl.fsf@gitster.dls.corp.google.com>
In-Reply-To: <s934mtwo0zv.fsf@mad-scientist.net>

Paul Smith <paul@mad-scientist.net> writes:

Show 8 quoted lines

>>> +	if test $(ls -a1 "$new_workdir/." | wc -l) -ne 2
>
>> I wonder if this check is portable for all platforms we care about,
>> but that is OK, as it should be so for the ones I think of and care
>> about ;-)
>
> Do you mean "." and ".." representing an empty directory?  That will
> work on any system where /bin/sh works, for sure.

Even on network mounts from esoteric filesystems and such?  When

    http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ls.html

mentions the "-A" option, it says:

    -A
        Write out all directory entries, including those whose names
        begin with a <period> ( '.' ) but excluding the entries dot
        and dot-dot (if they exist).

The "if they exist" part suggests, at least to me, that it is valid for a POSIX filesystem to lack these two (I suspect that one may be able to find a more definitive answer from other parts of the POSIX but I didn't bother).