Xref: utzoo comp.lang.c:26549 comp.sys.ibm.pc.programmer:236
Path: utzoo!attcan!telly!druid!darcy
From: darcy@druid.uucp (D'Arcy J.M. Cain)
Newsgroups: comp.lang.c,comp.sys.ibm.pc.programmer
Subject: Re: popen()
Summary: DOS is a single tasking system
Keywords: pipe DOS
Message-ID: <1990Mar4.142531.4231@druid.uucp>
Date: 4 Mar 90 14:25:31 GMT
References: <1503@loria.crin.fr>
Reply-To: darcy@druid.UUCP (D'Arcy J.M. Cain)
Followup-To: comp.sys.ibm.pc.programmer
Organization: D'Arcy Cain Consulting, West Hill, Ontario
Lines: 27

In article <1503@loria.crin.fr> anigbogu@loria.crin.fr (Julian Anigbogu) writes:
>Can some kind soul point me to where I can get a PC implementation of
>the Unix C popen() /* for handle to a pipe */. I manipulate huge
>rasterfiles(from a scanner) on a Sun and I adopted the policy of
>compressing all files to save disk space. I open them with
>popen("uncompress -c filename","r") so that they remain compressed on
>disk. 
>
> I now need to port the programs to DOS and to my chagrin my regular
>compiler doesn't implement a pipe open.
>
With good reason.  DOS is a single tasking system so you can't have a
program running without putting the current one on hold first.  The best
way to do what you want is to have the uncompression itself as a subroutine
that returns a specified number of bytes and just call it instead of a
read function.  This is the way I did it and it works just fine.  My function
returns one byte at a time although you could easily make the number of
bytes to return a parameter.

This is not really a C question so followups directed to
comp.sys.ibm.pc.programmer

-- 
D'Arcy J.M. Cain (darcy@druid)     |   Thank goodness we don't get all 
D'Arcy Cain Consulting             |   the government we pay for.
West Hill, Ontario, Canada         |
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