From: "John M. Aldrich" Newsgroups: comp.os.msdos.djgpp Subject: Re: Random implementation Date: Wed, 28 Jan 1998 20:01:52 -0500 Organization: Two pounds of chaos and a pinch of salt. Lines: 37 Message-ID: <34CFD500.219A@cs.com> References: <34CEAEE2 DOT 2DCF AT cs DOT com> <19980129003900 DOT TAA29842 AT ladder03 DOT news DOT aol DOT com> NNTP-Posting-Host: ppp213.cs.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Precedence: bulk Myknees wrote: > > I have tried to do random numbers before without success. Now I think I know > why. In the info documentation's alphabetical list, there is no mention of > srand(). And there's no cross reference to srand() from rand(). > [code snipped] > > But if this is right, how would a beginner find it out? (Besides, of course, > reading about it from an outside source.) srand() was omitted from the documentation, but srandom() was not. I noticed this, along with several other people, and there is a posted bug report correcting the docs. In any case, the seed functions probably ought to be mentioned in the docs for rand() and random(), and I think this will be done in v2.02. Your program is very strange. The use of bioskey() for example, is totally hardware-specific and makes no sense, when all you really need is getkey() or even getch(). Furthermore, calling srand() once for each call to rand() doesn't guarantee randomness; in fact it makes the results less random. You only need to seed a RNG once per program. As a final note, DJGPP's documentation isn't designed to teach standard C; it's designed to explain the functionality of the library code. I can see how it could be made clearer in some cases, but it would be wasteful to include a complete tutorial on random numbers in the library documentation when there are entire books devoted specifically to the subject. :-) -- --------------------------------------------------------------------- | John M. Aldrich | "Autocracy is based on the assumption| | aka Fighteer I | that one man is wiser than a million | | mailto:fighteer AT cs DOT com | men. Let's play that over again, | | http://www.cs.com/fighteer | too. Who decides?" - Lazarus Long | ---------------------------------------------------------------------