client.c

/*
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 */

/* 
 * File:   main.c
 * Author: root
 *
 * Created on March 6, 2018, 5:21 AM
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define SERVPORT 3333
#define MAXDATASIZE 100 /*每次最大数据传输量*/

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

    int sockfd, recvbytes;
    char buf[MAXDATASIZE];
    struct hostent *host;
    struct sockaddr_in serv_addr;
    if (argc < 2) {
        fprintf(stderr, "Please enter the server's hostname!\n");
        exit(1);
    }
    if ((host = gethostbyname(argv[1])) == NULL) {
        herror("gethostbyname error! ");
        exit(1);
    }
    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
        perror("socket create error! ");
        exit(1);
    }
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(SERVPORT);
    serv_addr.sin_addr = *((struct in_addr *) host->h_addr);
    bzero(&(serv_addr.sin_zero), 8);
    if (connect(sockfd, (struct sockaddr *) &serv_addr, sizeof (struct sockaddr)) == -1) {
        perror("connect error! ");
        exit(1);
    }
    if ((recvbytes = recv(sockfd, buf, MAXDATASIZE, 0)) == -1) {
        perror("recv error！");
        exit(1);
    }
    buf[recvbytes] = '\0';
    printf("收到： %s", buf);
    close(sockfd);
    return (EXIT_SUCCESS);
}