Xref: news2.mv.net comp.os.msdos.djgpp:2007
From: ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Returning from a system()
Date: 20 Mar 1996 22:27:30 GMT
Organization: The National Capital FreeNet
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Sender: ao950 AT freenet3 DOT carleton DOT ca (Paul Derbyshire)
Message-ID: <4iq0oi$29b@freenet-news.carleton.ca>
References: <DoH4Mz DOT ACo AT freenet DOT carleton DOT ca> <314f72b1 DOT sandmann AT clio DOT rice DOT edu>
Reply-To: ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Charles Sandmann (sandmann AT clio DOT rice DOT edu) writes:
>> Let's assume a program has used system() to launch a second program, which
>> is a DJGPP compiled program. Is there a way for the second program to
>> suspend execution and return to the first one *without* exiting? I.e. it
>> stays resident in memory, or is paged to disk. Also, how would the first
>> program return to the second?
> 
> If the first program hooks a software interrupt (in protected mode) and you
> write some GAS glue to handle the different CS/DS/SS issues (umm, maybe
> _go32_dpmi... routines?) then you could handle services for the child 
> program (when it issues interrupts in asm or via int86).  I was planning to 
> implement the multi-tasking signal library that way but I got too busy.

A lot of us would *love* to have such a library... hope you can find the
time to ipmlement it :-)

--
    .*.  "Clouds are not spheres, mountains are not cones, coastlines are not
 -()  <  circles, and bark is not smooth, nor does lightning travel in a
    `*'  straight line."    ,------------------------------------------------
         -- B. Mandelbrot  |  Paul Derbyshire (PGD) ao950 AT freenet DOT carleton DOT ca