C网络socket编程指南

C网络socket编程指南http://hi.baidu.com/zxhcloth/blog/item/12793a9beff870b5c8eaf475.html

client端

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
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#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>

#define PORT 4000

#define MAXDATASIZE 100
int
main(int argc, char *argv[])
{

int sockfd, numbytes;
char buf[MAXDATASIZE];
struct hostent *he;

struct sockaddr_in their_addr;

if (argc != 2)
{

fprintf(stderr,“usage: client hostname/n”);
exit(1);
}

if ((he=gethostbyname(argv[1])) == NULL)

herror(“gethostbyname”);
exit(1);
}
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {

perror(“socket”);
exit(1);
}

their_addr.sin_family = AF_INET;

their_addr.sin_port = htons(PORT);
their_addr.sin_addr = *((struct in_addr *)he->h_addr);

bzero(&(their_addr.sin_zero), 8);
if（connect(sockfd, (struct sockaddr *)&their_addr, sizeof(struct sockaddr)) == -1）
{

perror(“connect”);
exit(1);
}
if（(numbytes=recv(sockfd, buf, MAXDATASIZE, 0)) == -1）
{

perror(“recv”);
exit(1);
}
buf[numbytes] = ‘/0’;
printf(“Received: %s”,buf);

close(sockfd);
return 0;
}
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>

#define MYPORT 4000

#define BACKLOG 10
main()
{

int sock_fd, new_fd ;

struct sockaddr_in my_addr;

struct sockaddr_in their_addr;
int sin_size;
if ((sockfd =
- 162 - Linux网络编程
socket(AF_INET, SOCK_STREAM, 0)) == -1)
{

perror(“socket”);
exit(1);
}

my_addr.sin_family = AF_INET;

my_addr.sin_port = htons(MYPORT);

my_addr.sin_addr.s_addr = INADDR_ANY;

bzero(&(my_addr.sin_zero), 8);
if (bind(sockfd, (struct sockaddr *)&my_addr,
sizeof(struct sockaddr)) == -1)
{

perror(“bind”);
exit(1);
}

if (listen(sockfd, BACKLOG) == -1)
{

perror(“listen”);
exit(1);
}
while(1)
{

sin_size = sizeof(struct sockaddr_in);

第6 章 berkeley 套接字- 163 -
if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1)
{

perror(“accept”);
continue;
}

printf（“server: got connection from %s/n”, inet_ntoa(their_addr.sin_addr)）;

if (!fork())


if (send(new_fd, “Hello, world!/n”, 14, 0) == -1)
{

perror(“send”);
close(new_fd);
exit(0);
}

close(new_fd);
}