C语言整理之消息队列

最新推荐文章于 2025-11-13 00:15:00 发布

原创最新推荐文章于 2025-11-13 00:15:00 发布 · 9.9k 阅读

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本文介绍了如何使用C语言实现基于消息队列的进程间通信。通过`msgget`创建消息队列，`msgsnd`发送消息，`msgrcv`接收消息，以及`msgctl`控制消息队列。两个示例程序展示了发送和接收进程的逻辑，当接收到特定字符串"end"时，通信结束。

C语言消息队列

MsgQueue1.c

#include <sys/types.h>

#include <sys/ipc.h>

#include <sys/msg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <signal.h>

#define KEY 1234

struct msgbuf

{

long mtype; /* message type, must be > 0 */

char mbuf[100]; /* message data */

};

//typedef struct msgbuf buf;

int main()

{

int msgid,ret;

pid_t pid;

struct msgbuf buf;

msgid = msgget(KEY,IPC_CREAT | IPC_EXCL);

if(-1 == msgid)

{

perror("msgget");

exit(1);

}

pid = fork();

if(-1 == pid)

{

perror("fork");

exit(1);

}

else if(0 == pid)

{

while(1)

{

scanf("%s",buf.mbuf);

buf.mtype = 1;

ret = msgsnd(msgid,&buf,sizeof(buf.mbuf),0);

if(-1 == ret)

{

perror("msgsnd");

exit(1);

}

if(strncmp(buf.mbuf,"end",3) == 0)

{

buf.mtype = 2;

msgsnd(msgid,&buf,sizeof(buf.mbuf),0);

break;

}

memset(buf.mbuf,0,sizeof(buf.mbuf));

}

else

{

while(1)

{

memset(buf.mbuf,0,sizeof(buf.mbuf));

ret = msgrcv(msgid,&buf,sizeof(buf.mbuf),2,0);

if(-1 == ret)

{

perror("msgrcv");

exit(1);

}

if(strncmp(buf.mbuf,"end",3) == 0)

{

kill(pid,SIGKILL);

break;

}

printf("\t\t%s\n",buf.mbuf);

}

waitpid(pid,NULL,0);

}

msgctl(msgid,IPC_RMID,NULL);

return 0;

MsgQueue2.c

#include <sys/types.h>

#include <sys/ipc.h>

#include <sys/msg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <signal.h>

#define KEY 1234

struct msgbuf

{

long mtype; /* message type, must be > 0 */

char mbuf[100]; /* message data */

};

//typedef struct msgbuf buf;

int main()

{

int msgid,ret;

pid_t pid;

struct msgbuf buf;

msgid = msgget(KEY,0);

if(-1 == msgid)

{

perror("msgget");

exit(1);

}

pid = fork();

if(-1 == pid)

{

perror("fork");

exit(1);

}

else if(0 == pid)

{

while(1)

{

scanf("%s",buf.mbuf);

buf.mtype = 2;

ret = msgsnd(msgid,&buf,sizeof(buf.mbuf),0);

if(-1 == ret)

{

perror("msgsnd");

exit(1);

}

if(strncmp(buf.mbuf,"end",3) == 0)

{

buf.mtype = 2;

msgsnd(msgid,&buf,sizeof(buf.mbuf),0);

break;

}

memset(buf.mbuf,0,sizeof(buf.mbuf));

}

else

{

while(1)

{

memset(buf.mbuf,0,sizeof(buf.mbuf));

ret = msgrcv(msgid,&buf,sizeof(buf.mbuf),1,0);

if(-1 == ret)

{

perror("msgrcv");

exit(1);

}

if(strncmp(buf.mbuf,"end",3) == 0)

{

kill(pid,SIGKILL);

break;

}

printf("\t\t%s\n",buf.mbuf);

}

waitpid(pid,NULL,0);

}

msgctl(msgid,IPC_RMID,NULL);

return 0;

}