简单TCP服务端和客户端

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/errno.h>

int main(int argc, char *argv[])
{
int sockfd;
struct sockaddr_in my_addr, clt_addr;

if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
perror("socket");
return -1;
}

my_addr.sin_family = AF_INET;
my_addr.sin_port = htons(atoi(argv[2]));
inet_pton(AF_INET, argv[1], &my_addr.sin_addr);

if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(my_addr)) < 0)
{
perror("bind");
return -1;
}

listen(sockfd, 5);

int cltfd;
socklen_t addr_len;

while (cltfd = accept(sockfd, (struct sockaddr *)&clt_addr, &addr_len))
{
char *p = "hello client";
write(cltfd, p, strlen(p) + 1);
close(cltfd);
}

close(sockfd);
return 0;
}

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>

int main(int argc, char *argv[])
{
int sockfd;
struct sockaddr_in my_addr, srv_addr;

if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
perror("socket");
return -1;
}

/*
bzero(&my_addr, sizeof(my_addr));
my_addr.sin_family = AF_INET;
my_addr.sin_port = htons(atoi(argv[4]));
inet_pton(AF_INET, argv[3], &srv_addr.sin_addr);

//客户端可以调用bind，指定端口
if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(my_addr)) < 0)
{
perror("bind");
return -1;
}
*/

bzero(&srv_addr, sizeof(srv_addr));
srv_addr.sin_family = AF_INET;
srv_addr.sin_port = htons(atoi(argv[2]));
inet_pton(AF_INET, argv[1], &srv_addr.sin_addr);

if (connect(sockfd, (struct sockaddr *)&srv_addr, sizeof(srv_addr)) < 0)
{
perror("connect");
return -1;
}

int len = 0;
char buffer[1500];

while ((len = read(sockfd, buffer, sizeof(buffer))) > 0)
{
buffer[len-1] = '\0';
printf("%s\n", buffer);
}

close(sockfd);
return 0;
}