Linux发送与接收信息

receive:

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#define BUFFER_SIZE  512

struct message
{
    long msg_type;
    char msg_text[BUFFER_SIZE];
};

int main()
{
    int qid;
    key_t key;
    struct message msg;
    
    if((key=ftok(".",'a'))==-1)
    {
        perror("ftok");
        exit(1);
    }

    if((qid=msgget(key,IPC_CREAT|0666))==-1)
    {
        perror("msgget");
        exit(1);
    }

    printf("Open queue %d",qid);

    do
    {
        memset(msg.msg_text,0,BUFFER_SIZE);
        if(msgrcv(qid,(void*)&msg,BUFFER_SIZE,0,0)<0)
        {
            perror("msgrcv");
            exit(1);
        }

        printf("The message from process %d : %s",(int)msg.msg_type,msg.msg_text);
        
    }while(strncmp(msg.msg_text,"quit",4));

    if((msgctl(qid,IPC_RMID,NULL))<0)
    {
        perror("msgctl");
        exit(1);
    }
    
    exit(0);
    
}

send:

 

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#define BUFFER_SIZE 512


struct message{
    long msg_type;
    char msg_text[BUFFER_SIZE];
};

int main()
{
    int qid;
    key_t key;
    struct message msg;
    
    if((key=ftok(".",'a'))==-1)
    {
        perror("ftok");
        exit(1);
    }

    if((qid=msgget(key,IPC_CREAT|0666))==-1)
    {
        perror("msgget");
        exit(1);
    }

    printf("Open queue %d\n",qid);
    
    while(1)
    {
        printf("Enter some message to the queue:");
        if((fgets(msg.msg_text,BUFFER_SIZE,stdin))==NULL)
        {
            puts("No message");
            exit(1);
        }
        msg.msg_type=getpid();
        
        if((msgsnd(qid,&msg,strlen(msg.msg_text),0))<0)
        {
            perror("message posted");
            exit(1);
        }

        if(strncmp(msg.msg_text,"quit",4)==0)
        {
            break;
        }

    }
    exit(0);
}

gcc 两者

 #运行接收

./msgcrv 

#运行发送 

./msgsnd

#open two console to see the effect