p12-25.c

SUN Solaris8平台下进程间通信

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include "err_exit.h"
#define MAXMSG  1024
int main(void)
{
    int sock,size,nbytes;
    struct sockaddr_in name;
    char message[MAXMSG];
    /* 创建数据报套接字 */
    sock = socket(AF_INET, SOCK_DGRAM, 0);
    if (sock < 0) 
        err_exit("opening datagram socket");
    /* 用通配符命名该套接字 */
    bzero(&name,sizeof(name));
    name.sin_family = AF_INET;
    name.sin_addr.s_addr = htonl(INADDR_ANY);
    name.sin_port = htons(0);
    if (bind(sock, &name, sizeof(name))) 
        err_exit("binding datagram socket");
    /* 查出并打印系统赋给的端口值 */
    size = sizeof(name);
    if (getsockname(sock, &name, &size)) 
        err_exit("getting socket name");
    printf("Socket has port #%d\n", ntohs(name.sin_port));
    while(1){
        /* 从套接字读数据 */
        size = sizeof(name);
        nbytes = recvfrom(sock, message, MAXMSG, 0,(struct sockaddr *)&name, &size);
        if (nbytes < 0)
            err_exit("recfrom (server)");
        /* 打印出收到的消息 */
        printf("Server got message: %s\n", message);
        /* 将消息返回给发送者 */
        nbytes = sendto(sock, message, nbytes, 0,(struct sockaddr *)&name, size);
        if (nbytes < 0)
             err_exit("sendto(server)");
    }
}