Re: [wdiff-bugs] [PATCH] Non-seekable input [Savannah bug #25883]

[Denver Gingerich]

On Thu, Apr 2, 2009 at 3:42 AM, Martin von Gagern
<address@hidden> wrote:
> Hi!
>
> This is a copy of https://savannah.gnu.org/bugs/index.php?25883 as it
> seems that bugs posted in the savannah tracker are not automatically
> sent to this list as well.

Indeed that was the case.  They are sent directly to me, though I
hadn't responded.  I have added the mailing list to the "Global List:"
field in the "Bugs Tracker Administration: Set Notifications" section.
 If I understand Savannah right, this should send all bug updates to
this mailing list.  This seems to be a reasonable change given the low
volume of bug reports wdiff currently receives.

> I tend to use shell process substitutions a lot with diff. However, when
> I try to do the same with wdiff, I loose output without any indication
> that anything might have gone wrong. To test this, try the following:
> wdiff <(echo here foo there) <(echo here bar there)
>
> The primary cause of this is that this kind of input is not seekable.
> wdiff already contains some code to copy input to a temporary file, but
> it uses that method only for stdin.
>
> The attached patch checks whether or not a stream is seekable, and
> copies it to a temporary buffer if not. With this patch in place, the
> above command produces the expected output. As an added benefit, in
> cases where stdin is seekable, unnecessary buffering is avoided, though
> this case is probably rare.

Thanks very much for the patch.  I have done a cursory review of the
patch and it looks good.  I would like to do a more thorough review,
including testing, before including it in CVS.  Unfortunately, I'm
fairly busy right now so I might not get around to that for a few
days.  However, your patch seems small enough that I can squeeze it
into wdiff 0.6 (whenever that's released).

Denver
http://ossguy.com/