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rand.c
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rand.c
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/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: Implementation of rand() and srand().
*
****************************************************************************/
#include "variety.h"
#include <stdlib.h>
#include "rtdata.h"
#include "randnext.h"
#include "thread.h"
static unsigned long *initrandnext( void )
{
_INITRANDNEXT( RETURN_ARG( unsigned long *, NULL ) );
return( (unsigned long *)&_RWD_randnext );
}
_WCRTLINK int rand( void )
/************************/
{
unsigned long *randptr;
randptr = initrandnext();
if( randptr == NULL ) {
return( 0 );
}
*randptr = *randptr * 1103515245 + 12345;
return( (int)( (*randptr >> 16) & 0x7FFF ) );
}
_WCRTLINK void srand( unsigned int seed )
/***************************************/
{
unsigned long *randptr;
randptr = initrandnext();
if( randptr != NULL ) {
*randptr = seed;
}
}