oob_send.c

// 通过send()函数以及MSG_OOB标志发送带外数据
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
#include <errno.h>
#include "error_handling.h"

#define BUF_SIZE 30

int main(int argc, char *argv[])
{
    char buf[BUF_SIZE];
    struct sockaddr_in serv_addr;
    int sock;

    if (argc != 3)
    {
        printf("Usage: %s <port>\n", argv[0]);
        exit(1);
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = inet_addr(argv[1]);
    serv_addr.sin_port = htons(atoi(argv[2]));

    sock = socket(PF_INET, SOCK_STREAM, 0);
    if (sock == -1)
    {
        error_handling("socket() error: %s\n", strerror(errno));
    }

    if (connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1)
    {
        error_handling("connect() error: %s\n", strerror(errno));
    }

    write(sock, "123", strlen("123"));
    send(sock, "4", strlen("4"), MSG_OOB);
    write(sock, "567", strlen("567"));
    send(sock, "890", strlen("890"), MSG_OOB);

    close(sock);
    return 0;
}