From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: rand and random
Date: Tue, 2 Nov 1999 11:25:49 +0200
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On Tue, 2 Nov 1999, Damian Yerrick wrote:

> > `rand' returns a random integer between 0 and RAND_MAX.  The latter is
> > defined on stdlib.h, and is much larger than 32K.
> 
> I thought some C standard defined rand() as
> 
> #define RAND_MAX 0x7fff
> int rand(void)
> {
>   mySeed = (mySeed * 1103515245) + 12345;
>   return (mySeed & 0x7fff0000) >> 16;
> }

This is the *minimal* version of the generator recommended by the 
Standard.  It is compatible with the Standard's requirement that an int 
be at least 16-bit wide.

Most (if not all) 32-bit implementations provide a generator with
the full 32-bit range.