Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uwm.edu!srcsip!brubeck!galarnea
From: galarnea@SRC.Honeywell.COM (Jeff Galarneau)
Newsgroups: comp.lang.lisp
Subject: Re: Lisp - C problem
Message-ID: <52844@srcsip.UUCP>
Date: 8 Jan 90 16:41:29 GMT
References: <1026@prlhp1.prl.philips.co.uk>
Sender: news@src.honeywell.COM
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In-reply-to: walker@prlhp1.prl.philips.co.uk's message of 3 Jan 90 11:07:54 GMT

>  I'm running Sun Common Lisp 3.0.1 on mu Sparcstation and linking in code
>written in C. One of my c functions calls the sleep subroutine, but the call
>to sleep results in no process suspention. i.e. A sleep(5); call returns
>immediately. Has anybody experienced the same problem and found a solution?

I've run into similar problems, but instead of calling sleep, my C
functions called Oracle. At various times (completely at random) the C
routines would appear to hang and control would never return back to Lisp.
I found that the problem had to do with the Lucid Lisp scheduler.  I
wrapped all of my calls to C with the WITH-SCHEDULING-INHIBITED macro
and that solved my problem. I talked to a person at Lucid about this and he
said that as long as I don't explicitly define scheduler-dependent Lisp 
functions, I wouldn't experience any bad side-effects. So far he's been
right (knock on wood).

Jeff R. Galarneau                    Honeywell, Systems and Research Center
EMAIL: galarnea@src.honeywell.com    MN65-2100
PHONE: (612) 782-7205                3660 Technology Drive
                                     Minneapolis, MN 55418