From:	"Weiqi Gao" <weiqigao AT crl DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: fork????
Date:	15 Dec 1996 16:48:59 GMT
Organization:	CRL Dialup Internet Access
Lines:	25
Message-ID:	<01bbeaa7$bc5efb80$0f0171a5@weiqigao>
References:	<32B21822 DOT 4F80 AT novia DOT net>
NNTP-Posting-Host:	crl2.crl.com
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Dead_and_gone <alaric AT novia DOT net> wrote in article
<32B21822 DOT 4F80 AT novia DOT net>...
> does djgpp have a port of the fork function, I would code up a small test
> program but I have yet to figure out how to use fork ( I am mostly a dos
> programmer! )

Here's how you use fork():

int d;
i = fork();
printf("%d\n", i);

This will print two numbers: one is zero, by the child process, and the
other is the process id of the child process, printed by the parent
process.  You usually treat i < 0 (fork() failed, no new processes); i = 0
(child) and i > 0 (parent) differently.

As for DJGPP, the documentation says:
This function always returns -1 and sets `errno' to ENOMEM, as MS-DOS does
not support multiple processes.  It exists only to assist in porting Unix
programs.

-- 
Weiqi Gao
weiqigao AT crl DOT com

- Raw text -