利用消息队列机制实现进程之间的通信
打开或创建消息队列对象
int msgget(key_t key, int msgflg)
从消息队列接收消息
int msgrcv(int msqid, struct msgbuf *msgp, int msgsz, long msgtyp, int msgflg);
向消息队列发送消息
int msgsnd(int msqid, struct msgbuf *msgp, int msgsz, int msgflg);
消息队列控制操作
msgctl(int msqid, int cmd, struct msqid_ds *buf );
消息发送方：
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#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>
#include <unistd.h>
struct msg_st
{
long int msg_type;
char text[1024];
};
int main(){
int running = 1;
struct msg_st data;
char buffer[1024];
int msgid = -1 ;
msgid = msgget((key_t)1234,0666 | IPC_CREAT);
if (msgid==-1)
{
fprintf(stderr,"msgget error.");
exit(-1);
}
while (running){
printf("Enter your message:");
fgets(buffer,1024,stdin);
data.msg_type=1;
strcpy(data.text,buffer);
if(msgsnd(msgid, (void *)&data,1024,0) == -1){
fprintf(stderr,"message send failed.\n");
exit(-1);
}
if(strncmp(buffer,"quit",4) == 0){
running = 0;
sleep(1);
}
}
exit(0);
return 0;
}
消息接收方：
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#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>
#include <unistd.h>
struct msg_st
{
long int msg_type;
char text[1024];
};
int main(){
int running = 1;
struct msg_st data;
char buffer[1024];
int msgid = -1 ;
long int msgtype = 0;
msgid = msgget((key_t)1234,0666 | IPC_CREAT);
if (msgid==-1)
{
fprintf(stderr,"msgget error.");
exit(-1);
}
while (running){
if(msgrcv(msgid,(void*)&data,1024,msgtype,0)==-1){
fprintf(stderr,"get message failed with error\n");
exit(-1);
}
printf("Message Get:%s\n",data.text);
if(strncmp(data.text,"quit",4)==0){
running = 0;
}
}
if(msgctl(msgid,IPC_RMID,0)==-1){
// 删除消息对列
fprintf(stderr,"IPC_RMID Error.\n");
exit(-1);
}
exit(0);
return 0;
}
效果截图：
