#include <stdio.h>#include <unistd.h>#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <stdlib.h>#include <sys/ioctl.h>#include <linux/kd.h>#define SPEAKER_DEVICE "/dev/console"int main(int argc,char* argv[]){	//	int fd;	int i;		int freq;		if(argc!=2){		printf("Usage: %s frequence \n",argv[0]);		return 1;	}	freq=atoi(argv[1]);	if(freq<=0 || freq>10000){		printf("the frequence must be in the range from 0 to 10000\n");		return 1;	}	//	fd=open(SPEAKER_DEVICE,O_WRONLY);	if(fd==-1){		perror("Cannot open the speaker device");		return 1;	}	for(i=0;i<10;i++){		//		int set_freq=1190000/freq;		 		//		ioctl(fd,KIOCSOUND,set_freq);				//		usleep(200);		//		ioctl(fd,KIOCSOUND,0);				usleep(100);	}		return 0;}