Xref:	news2.mv.net comp.lang.c:67292 comp.os.msdos.djgpp:3697
From:	fmarcos AT jet DOT es (Fernando Marcos)
Newsgroups:	comp.lang.c,comp.os.msdos.djgpp
Subject:	Re: Use of random
Date:	Wed, 08 May 1996 23:11:18 GMT
Organization:	Servicio IBERNET (Telefonica Transmision de Datos)
Lines:	24
Message-ID:	<4ms6c2$hev@minerva.ibernet.es>
References:	<4mikhp$pa5 AT frodo DOT smartlink DOT net>
NNTP-Posting-Host:	info160.jet.es
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

nmarrone AT smartlink DOT net (Nicholas Marrone) wrote:

>program compiles and runs without error, but it gives me #s far larger
>than integers when I print out some results. I'm using DJGPP v2.

Nicholas:

As stated in the DJGPP docs, rand() returns a random number (weird
thing, isn't it?) between 0 and RAND_MAX. And RAND_MAX is defined in
STDLIB.H as 2147483647... which preciselly is an int. I guess from
what you write that you expect something upto 65535, which is the
maximum value reachable in a 16 bit environment. But remember, DJGPP
is a 32 bit compiler, so integers are 32 bit wide. That results is a
maximum capacity of +/-2^31 -1, which is (yaho!) 2147483647, or
0x7FFFFFFF.

If you need SHORT (16 bit) numbers, try shifting the rand result by
16:
	short wops;
	wops = rand() >> 16;

Fernando.

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