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From: woodcock@mentor.cc.purdue.edu (Bruce Sterling Woodcock)
Newsgroups: comp.unix.questions,comp.unix.programmer,comp.unix.wizards
Subject: How does one imitate SV_INTERRUPT?
Message-ID: <13619@mentor.cc.purdue.edu>
Date: 16 Jun 91 18:46:15 GMT
Followup-To: comp.unix.questions
Organization: Purdue University Computing Center
Lines: 25

The subject basically says it all.  I'm programming on a Sequent Symmetry
using Dynix V3.0.12 which, unfortunately, doesn't support the SV_INTERRUPT
flag.  Most systems after 4.2BSD have it.  To quote a 4.3BSD manual page:

     If a caught signal occurs during certain system  calls,  the
     call  is normally restarted.  The call can be forced to ter-
     minate prematurely with an EINTR error return by setting the
     SV_INTERRUPT   bit  in  the  flags  for  that  signal. [...]

Currently I'm trying to port a piece of software which uses SV_INTERRUPT,
but it is still not working correctly.  The code uses it to wait for a 
SIGCHLD, wait for the handler to execute, and then return.  However, I'm
having little success getting the code to do this properly without
SV_INTERRUPT.  What I want to know is if anyone can provide a routine to
simulate the behavoir of SV_INTERRUPT, or how to work around it.

Any help is appreciated.

Bruce

-- 
------------------------ woodcock@mentor.cc.purdue.edu ------------------------
Yes.  We fuck.  Often, and with great enjoyment of the act.  We aren't married,
we use birth control, we use interesting little toys on occasion.  We moan like
beasts in heat.  Life is *great*.  -- Garrett, ref. to Tif, on alt.brother-jed.