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From:	"MikeC" <My_address AT end DOT of DOT post>
Newsgroups:	comp.os.msdos.djgpp
Subject:	random() : What am I doing wrong?
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Message-ID:	<N1GBi.41236$S91.9560@newsfe7-win.ntli.net>
Date:	Thu, 30 Aug 2007 20:47:41 GMT
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Folks,

Here's an open invitation to make me feel foolish!

Here's the program :

#include <time.h>
#include <stdlib.h>

main()
{ long lng;

  lng = rawclock();
  printf("\nClock = %ld - ", lng);
  srand(lng);
  printf("Random numbers = %ld;  %ld;  %ld",random(),random(),random());
}

The idea is to seed the random number generator from the clock, so that the 
first call to random() will always produce a different result.

When I run the program several times, here's what it yields :

Clock = 1392294 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393105 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393314 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393420 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393471 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393512 - Random numbers = 1027100827;  143302914;  2078917053
Clock = 1393548 - Random numbers = 1027100827;  143302914;  2078917053

The 'random' numbers are the same every time I run the program, yet they are 
being seeded be a clock value that is different each time.  I guess the wood 
is there somewhere, but the trees are getting in the way.

Incidentally, I'm running Windows 2000, SP4.

Advance thanks,

MikeC.
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