Re: fork() Problem?

Rogier Wolff (R.E.Wolff@BitWizard.nl)
Wed, 5 May 1999 18:24:14 +0200 (MEST)

David Miller wrote:
> Date: Wed, 5 May 1999 09:19:54 +0300 (EEST)
> From: Yavuz Selim Komur <komur@albatros.bcc.bilkent.edu.tr>
>
> Problem is sequence error.
>
> if (pid = fork())
> printf("Main Program");
> else
> printf("Child Program");
>
> it's clear?
>
> So Linux runs the child before the parent in your test runs, whereas
> the opposite is true on other systems. Is this a problem?

This is a classical optimization: In 99 out of 100 cases, the "child"
will perform an "exec" in a few milliseconds. The possibility is there
that that will require disk IO. At that time the parent will get the
chance to do its thingy: run on until the "wait" system call (about 98
percent of the cases...)

Roger.

-- 
** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 **
*-- BitWizard writes Linux device drivers for any device you may have! --*
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