Path: utzoo!attcan!uunet!munnari.oz.au!brolga!bunyip.cc.uq.oz.au!marlin.jcu.edu.au!glmwc
From: glmwc@marlin.jcu.edu.au (Matt Crowd)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: C questions (again)
Summary: Is it really so strange? (sorry Morrissey!)
Message-ID: <1991Feb11.110531.3898@marlin.jcu.edu.au>
Date: 11 Feb 91 11:05:31 GMT
References: <1991Feb7.114348.10577@marlin.jcu.edu.au> <18a64c31.ARN0d59@swinjm.UUCP>
Organization: James Cook University of North Queensland
Lines: 55

In article <18a64c31.ARN0d59@swinjm.UUCP> forgeas@swinjm.UUCP (Jean-Michel Forgeas) writes:
>In article <1991Feb7.114348.10577@marlin.jcu.edu.au>, Matt Crowd writes:
>
>>       input = (struct FileHandle *) Input(); // get filehandle of stdin
>>       printf("This is program 1!\n");
>>       Execute("program2",input,0); // run program2
>                                 ^^-----------------------------it's here
>>       printf("Because of something very wierd, this line "
>>       "will not be printed.  I do not know why.\n");
>
>The parameters of Execute() are: ( "program name", input, output )
>Since your "program2" does 'printf' it needs an output. It has not,
>so it prints 'into the air'... and hangs.
>This should work:
>        Execute("program2",input,Output());

No, that doesn't work.  Execute takes parameters to redirect
stdin/stdout, but if you pass 0 it uses the standard ones.  Believe
me, I've tried everything.  I've now tried the console.device only
to find out you have to do the arrow keys yourself for some strange
reason (surely an option was in order!).  Now I'm openning a CON: window with

file = Open ("CON:0/0/640/400",MODE_OLDFILE);

But that doesn't seem to work with  
Execute("dir",file,file) to get dir to appear in my own window.  This
is because Execute reads the file until EOF, which doesn't occur, so
it gives a CLI prompt in my window! 


And as this is part of a larger program (similar to creating
your own shell) I can't just redirect to a temporary file and display it.
So it seems Execute is very CLIish (yes I just made that word up).
I've been looking through the system and I'm pretty sure I can hack the OS
to make it work properly, but I shouldn't have to.  Under 2.0 the System call
looks like it can take a parameter to a User shell, but I'm not sure
if that's what I need, or really even what it is.  Does anyone out
there have any source code examples of using System(), which I
think might have the same limitations, or other ways of redirecting
commands to your own window while preserving input/output? 

Idea -
Would avoiding SAS C calls, and having both programs run in the CLI,
using Read && Write for i/o and getting the filehandles with Input()/
Output() solve the proglem?  I think it might, so I'll try that... 
 
>                                     \___/
>Jean-Michel Forgeas                   \-/
>cbmvax!cbmehq!cbmfra!swinjm!forgeas    |    The Software Winery
>                                      -^-
>                           And, where is the universe ?

Thanks,
Colin Adams
(soon to be an Amiga Developer, maybe it might help!)