Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!sdd.hp.com!caen!kuhub.cc.ukans.edu!markv
From: markv@kuhub.cc.ukans.edu
Newsgroups: comp.sys.amiga.programmer
Subject: Re: C questions (again)
Message-ID: <28623.27bc0e9d@kuhub.cc.ukans.edu>
Date: 15 Feb 91 22:38:52 GMT
References: <1991Feb7.114348.10577@marlin.jcu.edu.au> <18a64c31.ARN0d59@swinjm.UUCP> <1991Feb11.110531.3898@marlin.jcu.edu.au>
Organization: University of Kansas Academic Computing Services
Lines: 105

In article <1991Feb11.110531.3898@marlin.jcu.edu.au>, glmwc@marlin.jcu.edu.au (Matt Crowd) writes:
> 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.

If you using SAS/Lattice and main(), then the startup will Open a CON:
window for stdin/out.  I'm still not sure why this doesn't work though.

>>This should work:
>>        Execute("program2",input,Output());

Have you tried:
	In = Open("*", MODE_NEWFILE);
	Out = Open("*", MODE_NEWFILE);

	Execute("program2", In, Out);

It might be that the original Input() and/or Output() were opened
MODE_NEWFILE and dont like being shared, but I'm not a real DOS guru.
 
> 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

Hmm, I could be off, but if your using a CON: window you wont get
arrows, only RAW: gets arrows, FKeys, etc.
 
> 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! 

What about:	file = Open("*", MODE_OLDFILE);

to get your current window.

As a side note the Input and Output parameters to Execute() must have
real DevProc()s associated with them (therefor NIL: will croak for
one).
  
> 
> 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).

Yes, on the Amiga, (1.3 and before at least), there are some important
differences between CLI and non-CLI processes.  Just look at the CLI
struct, etc for that.  And yes, Execute is very CLIish, because it
creates CLI type processes.

> 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... 

Or, using SAS C, use _tinymain() and the amiga.lib I/O to get IO calls
that use Amiga file handles.

>  
>>                                     \___/
>>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!)

I'm one and I'm clueless here.

I remember having similar problems when I tried hack up a jorunalizing
facility for a CLI window.  Good luck,

-- 
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