*BSD News Article 17280


Return to BSD News archive

Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!noc.near.net!das-news.harvard.edu!husc-news.harvard.edu!husc11.harvard.edu!jiu1
Newsgroups: comp.unix.bsd
Subject: IPC on RS/6000 - PLEASE HELP!
Message-ID: <1993Jun17.233643.25055@husc3.harvard.edu>
From: jiu1@husc11.harvard.edu (Haibin Jiu)
Date: 17 Jun 93 23:36:42 EDT
Organization: Harvard University Science Center
Nntp-Posting-Host: husc11.harvard.edu
Lines: 23

Hi!  I have a question about using IPC on the RS/6000 workstation.

We developed a program using UDP protocol to communicate among a group
of worker processes.  The program worked fine on the Sun, but somehow
stalked on the RS/6000.

The problem is this:  We use the SIGIO signal to find out whether there
is something waiting at the socket.  So whenver a worker process sends
a message to another process (on a remote node), the latter will get a
SIGIO (#23) signal, as defined in 4.3BSD IPC facilities.  Now this
works perfectly okay on the Sun Sparcs, but on the RS/6000s somehow this
signal is not present, that is, it is either not generated or not detected,
the target process is simply ignorant of the arrivals of messages.

I checked AIX (IBM's implementation of UNIX) man pages and tried out
an asynchronous I/O program from W.Richard Stevens' popular text, UNIX
Network Programming (from Chap. 6).  The sample prog. worked on Suns, but
didn't work on the RS/6000s, for the reason stated above.

Would anyone have an answer for this mystery?  An e-mail reply will be
greatly appreciated.

hbJ