Re: Linux doing "cooperative multitasking"?

Tim Wright (
Wed, 27 Nov 1996 12:24:26 PST

OK, here's the expanded answer, (Joost Witteveen already gave it briefly :-)

Typing '^Z' results in sending SIGTSTP to the foreground process (group).
The process in question is at liberty to catch or even ignore this.
Netscape seems to sometimes get itself into a state where it takes a
(long) time to respond. This could be deemed a bug in Netscape as it's
bad form to ignore a users request to suspend for and extended time.

You can forcibly stop it by use of 'kill -STOP pid' from another tty (although
whether this is wise is another matter).

This has nothing to do with co-operative multitasking, or X11 or anything
else like that. It's simply the way '^Z' and SIGTSTP are handled.

Can we put this one to bed please - it's not a kernel related question.



In message <>,Uwe Bonn
es writes:
> Hallo,
> I use Netscape Version 3.01 on Linux 2.0.25 and XFree 86-3.1.2.F. (Well now
> it is Xfree 86-3.2)
> At present I preload and, but I had the problems
> with and too. Here my problem ( or better
> observation).
> I start netscape on an rxvt-Term. I forgot to send it in the Background by
> not giving "&" at the end of the command line. So I hit "^Z" on the terminal
> I
> started netscape. Nothing happens for a long time or at all.
> Is Linux doing only "cooperative multitasking"?
> I know that that Netscape is broken in many regards, but anyways, i thought
> that Linux is doing preemtive multitasking to cope with such broken
> programs. And a "^C" on the controlling terminal is honored.
> Is my setup broken? Or is there another problem.
> Thanks
> (if you get tis message twice, sorry, sent it yesterday to
>, didn't get something back, so I resent
> it to linux-kernel)
> --
> Uwe Bonnes
> Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
> --------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------

Tim Wright, Worldwide Technical Services,         |  Email:
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