Re: open-input-output-process, open-input-output-pipe

[Gary Houston]

> From: Rob Browning <address@hidden>
> Date: 19 Mar 2001 12:56:53 -0600
> 
> Mikael Djurfeldt <address@hidden> writes:
> 
> > I'd find something like the patch below useful.  The procedures
> > below return a pair of an input and output port instead of the
> > input-output port which is stated in the comment.  How would one go
> > about implementing it as intended, i.e. with an input-output-port?
> 
> I agree that having something like this would be useful since I wrote
> something very similar lately :>.

Ha, I wonder now if is there anyone on guile-devel who has not :)

> I originally implemented it with one io-port too, but for some reason
> (probably a misunderstanding on my part), never did quite get it to
> work right.  In the end I settled on returning (list pid to-child-port
> from-child-port stderr-port).  This seems perhaps better than just one
> two-way port anyway, if you want to handle stderr.  (Actually, right
> now, in my code, stderr isn't really hooked up, yet).

I forgot earlier to mention ptys.  If we got pty support back into
guile-core it would probably be the best one-port solution.  ptys
help with programs like ftp clients that act differently when taking
input from a pipe.

> > +        (set-batch-mode?! #t)
> > +        (close-all-ports-except (cdr from) (car to))
> 
> Didn't know about these, but they're obviously appropriate...

close-all-ports-except is now deprecated in CVS.

> > +    (pipe-guardian (car port))
> 
> I didn't realize we had pipe-guardians.  Is there any documentation
> around?

Take a look at ice-9/popen.scm in CVS.  Mikaels code is written to go
in there.

> > +    (hashq-set! port/pid-table (car port) (cdr port/pid))
> 
> Another bit I didn't know I needed to add.  Is there documentation for
> how this is supposed to be handled?

Take a look at ice-9/popen.scm in CVS.