Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: mdb@silvlis.com (Mark D. Baushke)
Newsgroups: comp.sys.sun
Subject: Re: problem using sunview window + reading tty from a child process
Message-ID: <8902141733.AA17970@amadeus.silvlis.com>
Date: 23 Feb 89 13:44:20 GMT
Sender: usenet@rice.edu
Organization: Sun-Spots
Lines: 67
Approved: Sun-Spots@rice.edu
Original-Date: Tue, 14 Feb 89 09:33:18 PST
X-Sun-Spots-Digest: Volume 7, Issue 169, message 4 of 12

Please note that due to an apparent time warp of some kind, my original
question was published after its solution was published.

The original question was in

        Sun-Spots Digest: Volume 7, Issue 153, message 2 of 16

the solution was published in

        Sun-Spots Digest: Volume 7, Issue 144, message 5 of 9

If possible, please either delete sunviewhelp.shar or include the solution
in that file.

[[ I wonder how that happened.  Sorry for the confusion.  I have removed
the shar file.  --wnl ]]

Problem/solution summary:

        Using stdin before creating a window and then again after the
        window no longer existed from a child process was not working.

        The problem is that sunview programs change process groups in
        the first call to window_create().  The work around should be
        something like this:

                int saved_pgrp;
                saved_pgrp = getpgrp(getpid());

                frame = window_create (NULL,FRAME,0);

                setpgrp(getpid(), saved_pgrp);


Thank you for anyone who may have obtained the shar file to try and help
me out.

Mark D. Baushke                 Internet:    mdb%silvlis.com@sun.com
Silvar-Lisco, Inc.              Nameservers: mdb@silvlis.com
1080 Marsh Road                 Usenet:      {pyramid,sgi,sun}!silvlis!mdb
Menlo Park, CA 94025-1053       Telephone:   +1 415 853-6411 / +1 415 969-8328

---------- Forwarded message From: sun!hvr (Heather Rose)

Mark,

The problem you're running into is that sunview programs change process
groups in the first call to window_create().  You can work around this
with something like this:

        int saved_pgrp;
        saved_pgrp = getpgrp(getpid());

        frame = window_create (NULL,FRAME,0);

        setpgrp(getpid(), saved_pgrp);

For just your first call to window_create().  Please try this and if it
does not work out for you, please get back to me by 1/31/89....

Also, if you use vfork instead you can save on some temporary swap space.
See the man page on fork.

Regards,

Heather Rose
U.S. Answer Center