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Mail Archives: djgpp/1998/02/02/22:52:01

From: Myknees AT aol DOT com
Message-ID: <aaab8c0c.34d68ffd@aol.com>
Date: Mon, 2 Feb 1998 22:33:15 EST
To: eliz AT is DOT elta DOT co DOT il
Cc: dj AT delorie DOT com, djgpp AT delorie DOT com
Mime-Version: 1.0
Subject: Re: Documentation [was Re: Random implementation]

The latest changes: leaving out reference to source; fixed typo; ran diff from
djgpp.env's directory; called the new version rand.txh; removed extra texi
markup from example.

There's no hypertext link to the docs (that aren't there) for srand(), though.

*** src/libc/ansi/stdlib/rand.old	Mon Jul 10 01:39:56 1995
--- src/libc/ansi/stdlib/rand.txh	Mon Feb  2 22:21:20 1998
***************
*** 1,24 ****
  @node rand, random number
! @subheading Syntax
  
  @example
  #include <stdlib.h>
  
  int rand(void);
  @end example
  
  @subheading Description
  
  Returns a pseudo-random number from zero to @code{RAND_MAX}. 
  
  @subheading Return Value
  
! The number.
  
  @subheading Example
  
  @example
  /* random pause */
  for (i=rand(); i; i--);
  @end example
  
--- 1,48 ----
  @node rand, random number
! n AT subheading Syntax
  
  @example
  #include <stdlib.h>
  
  int rand(void);
+ void srand(unsigned _seed);
  @end example
  
  @subheading Description
  
  Returns a pseudo-random number from zero to @code{RAND_MAX}. 
  
+ This function has its own default seed but may also be seeded with the
+ function @code{srand}.  It is
+ only necessary to use @code{srand} in the following cases:
+ 
+ @itemize @bullet
+ 
+ @item
+ 
+ If the pseudo-random sequence must be different each time you run the
+ program
+ 
+ @item
+ 
+ If the sequence must continue from the same place it ended on some
+ previous run
+ 
+ @end itemize
+ 
  @subheading Return Value
  
! The pseudo-random number.
  
  @subheading Example
  
  @example
  /* random pause */
  for (i=rand(); i; i--);
+ @end example
+ 
+ @example
+ /* seed rand with current time */
+ srand(time(0));
  @end example
  

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