slbeep.c

C标准库源代码

/***
*slbeep.c - Sleep and beep
*
*       Copyright (c) 1991-1997, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines _sleep() and _beep()
*
*******************************************************************************/

#include <cruntime.h>
#include <oscalls.h>
#include <stdlib.h>

/***
*void _sleep(duration) - Length of sleep
*
*Purpose:
*
*Entry:
*       unsigned long duration - length of sleep in milliseconds or
*       one of the following special values:
*
*           _SLEEP_MINIMUM - Sends a yield message without any delay
*           _SLEEP_FOREVER - Never return
*
*Exit:
*       None
*
*Exceptions:
*
*******************************************************************************/

void __cdecl _sleep(unsigned long dwDuration)
{

    if (dwDuration == 0) {
        dwDuration++;
    }
    Sleep(dwDuration);

}

/***
*void _beep(frequency, duration) - Length of sleep
*
*Purpose:
*
*Entry:
*       unsigned frequency - frequency in hertz
*       unsigned duration - length of beep in milliseconds
*
*Exit:
*       None
*
*Exceptions:
*
*******************************************************************************/

void __cdecl _beep(unsigned dwFrequency, unsigned dwDuration)
{
    Beep(dwFrequency, dwDuration);
}