Date: Sun, 17 May 1998 14:23:35 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Paul Derbyshire <pderbysh AT usa DOT net>
cc: djgpp AT delorie DOT com
Subject: Re: Threading and asynchronous processes
In-Reply-To: <8R571.1176$qR3.4113921@news20.bellglobal.com>
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On Sat, 16 May 1998, Paul Derbyshire wrote:

> 1. Can this form of threading launch a separate asynchronous process safely,
> e.g. a shell to command.com to display a directory as a simple
> example? If there are constraints, which of these will work?

I really cannot see how this can be answered unless you describe the
implementation of threading you have in mind.  Each implementation
will have different constraints.

For example, one possible implementation is to use the DJGPP signals
for switching threads.  In this case, issuing any real-mode call, like
a DOS function (including the one required to run a child process)
will effectively stop multi-threading, since signals in DJGPP are
suspended until real-mode calls return.