Re: Bug#677865: Re: Bug#677865: dpkg-gencontrol warns about 'File::FcntlLock not available'

[Guillem Jover <guillem@debian.org>]

Hi!

On Fri, 2014-05-16 at 11:05:35 +0200, Jens Thoms Toerring wrote:
> > Long term what I think would be best would be to get File::FcntlLock
> > into the perl core distribution, preferably upstream, but I'm not sure
> > how such proposals are handled there and if something like that would
> > be feasible, Jens what do you think? And/or would that be possible in
> > Debian, maybe in the interim or regardless of perl core upstream?
> 
> I've never considered trying to get this module included into
> the Perl core distribution (and I also wouldn't know how to
> get started with something like that;-)

I'd assume a proposal needs to be sent to perl5-porters? But I've
skimmed a bit over its archives, and I don't see anything obvious
there. The debian-perl folks will know most probably.

> Unfortunately, I also
> don't see any way to do things without XS since the flock
> structure that must be passed to fcntl(2) can be quite dif-
> ferent on different systems, both concerning the number and
> ordering of its members as well as the sizes of them:-( I
> would love to hear ideas on how to do it differently, i.e.
> with Perl-only methods!

Yeah, I don't see any other way either of doing it with pure perl.

> As far as I can see I can't contribute anything useful here,
> sorry. If someone has some pointers on how to go about getting
> it into the Perl core distribution I would try that, though I'd
> rather likely need a lot of very good arguments to convince peo-
> ple deciding about such things - some of you might be in a better
> situation for that. But they might argue that you already can get
> fcntl(2) used for locking instead of flock(2) by building Perl with
> "-Ud_flock" (don't ask me why that's not the default anyway;-)
> Perhaps building the Perl version distributed with Debian with
> that option might be another solution?

I don't think switching perl in Debian to use fcntl(2) would be a good
idea as the perl documentation states that this would change the
semantics for the flock perl function too, which could easily break
code around.

Thanks,
Guillem