消息队列

1.mq_open等相关系统函数使用

#include <iostream>
#include <algorithm>
#include <cstring>
#include <mqueue.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
using namespace std;

int main(int argc, char **argv)
{

    mqd_t mqd;
    struct mq_attr mqAttr;
    mqAttr.mq_maxmsg = 100;
    mqAttr.mq_msgsize = 100;
    int flag = O_RDWR | O_CREAT;
    const char *pPath = "/myqueue.1234";
    if (-1 == (mqd = mq_open(pPath, flag, 0666, NULL)))
    {
        cout << "create mq failed!" << endl;
        cout << errno << endl;
    }
    int len = 12;
    char buff[12] = "abcde";
    mq_send(mqd, buff, len, 2);
    mq_getattr(mqd, &mqAttr);
    cout << "maxsize:" << mqAttr.mq_msgsize << endl;
    char *recvBuff = new char[mqAttr.mq_msgsize];
    unsigned int priority = 0;
    ssize_t recNum = mq_receive(mqd, recvBuff, 8192, &priority);
    cout << recvBuff << endl;
    delete [] recvBuff;
    recvBuff = NULL;

    mq_unlink(pPath);
    return 0;
}