#include <stdio.h>#include <sys/types.h>#include <sys/ipc.h>#include <sys/msg.h>typedef struct {        long mtype;        char mtext[BUFSIZ];}msg_info;int recv_msg(int msqid,int msg_type,char* msg){	int result;	msg_info buffer;	result=msgrcv(msqid,&buffer,BUFSIZ,msg_type,0);	if(result==-1)		perror("cannot receive message from the queue");	strcpy(msg,buffer.mtext);		return result;}int main(int argc,char* argv[]){	char buf[BUFSIZ];	int msqid;	int msg_type;	int result;	if(argc!=3){		printf("Usage: %s msqid message_type\n");		return -1;	}		msqid=atoi(argv[1]);	msg_type=atoi(argv[2]);		result=recv_msg(msqid,msg_type,buf);	if(result==-1){		printf("cannot get message");		return -1;	}else		printf("message queue id: %d message type : %d message : %s\n",msqid,msg_type,buf);	return 0;}