#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 creat_msg_queue(){        key_t key;        int proj_id;        int msqid;        struct msqid_ds buffer;        proj_id=2;        key=ftok("/home/program",proj_id);        if(key==-1){                perror("cannot generate the IPC key");                return -1;        }        msqid=msgget(key,IPC_CREAT | 0660);        if(msqid==-1){                perror("cannot create message queue resource");                return -1;        }	return msqid;}int send_msg(int msqid,char* msg){	int result;		msg_info buf;		buf.mtype=100;	strcpy(buf.mtext,msg);		result=msgsnd(msqid,&buf,strlen(msg),0);	if(result==-1)		perror("cannot send message to the message queue");		return result;}int show_msg_queue_stat(int msqid){	struct msqid_ds buffer;	int flg;	flg=msgctl(msqid,IPC_STAT,&buffer);	if(flg==-1){		perror("cannot get status of the message queue");		return -1;	}	        printf("=======Message Queue Info========\n");        printf("effective user id : %d \n",buffer.msg_perm.uid);        printf("effective group id: %d \n",buffer.msg_perm.gid);        printf("message queue's creator user id : %d \n",buffer.msg_perm.cuid);        printf("message queue's creator group id : %d \n",buffer.msg_perm.cgid);        printf("access mode : %x\n",buffer.msg_perm.mode);        printf("Maximum number of bytes allowed in message queue : %d \n",buffer.msg_qbytes);        printf("Current number of bytes in message queue (non-standard) : %d \n",buffer.__msg_cbytes);        printf("Current number of messages in message queue : %d \n",buffer.msg_qnum);	return 0;}int main(int argc,char* argv[]){		int msqid;	if(msqid=creat_msg_queue()<0){		printf("create msg queue fail");		return -1;	}	if(send_msg(msqid,"test message")<0){		printf("send message fail");		return -1;	}		if(show_msg_queue_stat(msqid)<0){		printf("show message queue fail");		return -1;	}	return 0;}