sound() in c

sound(),nosound()
sound turns the PC speaker on at the specified frequency
nosound turns the PC speaker off
Declaration:
void sound(unsigned frequency);
void nosound(void);
Remarks:
sound turns on the PC's speaker at a given frequency.
nosound turns the speaker off after it has been turned on by a call to sound.
frequency specifies the frequency of the sound in hertz (cycles per second).
Return Value:
None
Example :

#include <dos.h>  int main(void)  {     sound(7);     delay(10000);     nosound();     return 0;  }

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