Re: [bug-gnulib] request for new modules for portable pseudo-terminal allocation functions

[Claudio Fontana]

--- Bruno Haible <address@hidden> wrote:

> Hello,
> 
> > allocating pseudo-terminals in a portable way is a
> nightmare.
> 
> I agree. You also find some source code in this
> direction in glibc,

I found the relevant source in glibc much more
readable than my previous attempt with expect.

> in xterm (horrible mess of #ifdefs), in
> kdebase/konsole, in rxvt,
> in gnome-terminal, ...
> 
> > It would be nice if gnulib included portable
> > replacements for GNU C library functions getpt,
> > grantpt, unlockpt, ptsname, ptsname_r, openpty,
> > forkpty,
> 
> Is this API sufficient?

I think so. The really needed op (for me) is to get a
master-slave pair (openpty). I will implement
something similar to forkpty myself, because forkpty
closes 1 and 2 to redirect them to the
pseudo-terminal, while I need to redirect them to
pipes, and only 0 should refer to the pty (I hope that
will work portably).

> The example in the glibc
> manual indicates that
> some STREAMS operations are necessary as well, no?

As far as I know (which is not that far), it is
something specific of ptsname and ptsname_r (if you
want to open the pseudoterminals from their name
yourself). My guess is that the higher level APIs,
openpty and forkpty, are unaffected.
 
> The usual way for some code to come into gnulib is
> that someone who needs
> it writes it, and then submits it into gnulib.

Someone with a stronger knowledge of the glibc than me
could maybe extract those functions from the codebase.

If no one steps up in some time, I will give it a try
(since I need it to complete libsrcinst).

Thanks for pointing at the glibc sources, they helped
me understand some things better.

Claudio


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com