[Chicken-users] Wierd behaviour of process.

[Robin Lee Powell]

In the middle of the Scheme binding I wrote for mooix, I call
process (from posix) for IPC.  The system is, in total, very
complex; so much so that I don't even know where to start to at
making a pared-down example.

So, I'll describe the behaviour.

I run process in the same way (see
http://paste.lisp.org/display/35085 for my code; at least, that's
what it looked like after I had hacked it for a while trying to
solve this problem) quite a number of times.  At one point, process
calls a Perl script that is set sticky (not that I think that
matters, but there you are) that returns no output at all.  process
correctly sees it as returning no output.  The *next* call to
process appends a string, call it StringX, to the real output of the
process it calls, for no apparent reason.

StringX happens to be the mooix-internal name of the object whose
mooix method was the Perl script I mentioned.  I have no idea where
it's coming from in this interaction; it's not passed through
process at any point that I can see.

The really wierd part:

This only happens if the second argument to process is filled.  I
was filling it with (list "") just to avoid calling the shell
(security warm-fuzzies).  But now I've had to take that out, so this
will work.

This may very well *not* be a Chicken issue: as I said, the system
is very complex and, in particular, hacks a number of libc calls,
including exec*.

However, I've never seen this behaviour before, using either C or
Perl code in mooix, so... *shrug*

Any help/suggestions/things to try welcome, although I do have a
workaround.

-Robin

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