Re: [PATCH] commit: ensure correct permissions of the commit message

> On Sun, Dec 20, 2015 at 05:31:48PM -0800, Junio C Hamano wrote:
>
>> Actually, we do not even _need_ a sharedness for this ephemeral
>> file.  The additional "adjust-shared-perm" is merely a workaround
>> for the fact the next person cannot write into it when it is left
>> behind, and because we do not want to remove it when we are done.
>> 
>> That does not measn that the next person cannot remove it when she
>> finds there is a file there left behind.  So alternatively, we could
>> do something like this, perhaps?
>> 
>>         FILE *fopen_forcibly(const char *path, const char *mode)
>>         {
>>                 FILE *ret = fopen(path, mode);
>> 
>>                 if (!ret && errno == EPERM) {
>>                         if (!unlink(path))
>>                                 ret = fopen(path, mode);
>>                         else
>>                                 errno = EPERM;
>>                 }
>>                 return ret;
>>         }
>
> Yeah, I think that is a much nicer solution for this case. It should
> work even in a shared repo, since we set the permissions for the
> surrounding $GIT_DIR appropriately[1].
>
> I guess it would not apply to any files that do not want to truncate the
> existing contents. Probably it should drop the "mode" parameter at all,
> since anything but "w" would be crazy?