Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!rpi!crdgw1!pookie!barnettj
From: barnettj@pookie.crd.ge.com (Janet A Barnett)
Newsgroups: comp.sys.amiga.programmer
Subject: Launch and Switch Fields in the Task Structure
Summary: What are they for?
Keywords: multitasking launch switch system programming
Message-ID: <17933@crdgw1.crd.ge.com>
Date: 27 Mar 91 02:49:12 GMT
Sender: barnett@crdgw1.crd.ge.com
Organization: General Electric Corporate R&D Center
Lines: 13

What are the tc_launch and tc_switch fields used for?

I'm writting some numerical software for my amiga and would like to
have separate tasks make use of the 68882.  The SAS/C compiler manual
warns against this, indicating that the operating system does not
properly handle sharing of the coprocessor between tasks.  So, my
question is: can the task launch and switch fields be used to save the
state of the coprocessor when a task loses the CPU and restore it when
the CPU is regained? For fun, I tried poking the address of routines
internal to my code in these fields; visits from the GURU ensued.
Meditation has yielded no fruitful thoughts.

AB