Network client/sever (一)

摘自 <<Beginning Linux Programming_4th>>

chapter 15 Sockets

1  header files

#include <sys/types.h>
#include <sysy/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

2  socket

int main ()
{
    int  sockfd;
    int  len;
    struct  sockaddr_in  address;
    int  result;
    char  ch = ‘A‘;

    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = inet_addr("127.0.0.1");
    address.sin_port = htons(9734);
    len = sizeof(address);

3  connect

result = connect(sockfd, (struct sockaddr*) &address, len);
if(result == -1)
{
    perror("oops: client");
    exit(1);
}

4  read/write

    write(sockfd, &ch, 1);
    read(sockfd, &ch, 1);

    printf("char from server = %c\n", ch);

    close(sockfd);

    exit(0);

}