C语言Linux下的Socket 编程(TCP)

来源：互联网发布：linux 连接oracle 编辑：程序博客网时间：2024/05/21 10:32

(1) Client.cpp

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

void error(const char *msg)
{
perror(msg);
exit(0);
}

int main(int argc, char *argv[])
{
int sockfd, portno, n;
struct sockaddr_in serv_addr;
char buffer[256];
char *server_addr = argv[1];

if (argc < 3) {
fprintf(stderr,"usage %s port\n", argv[0]);
exit(0);
}

portno = atoi(argv[2]);
sockfd = socket(AF_INET, SOCK_STREAM, 0);

if (sockfd < 0)
error("ERROR opening socket");

bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
// bcopy((char *)server->h_addr,
// (char *)&serv_addr.sin_addr.s_addr, server->h_length);
serv_addr.sin_addr.s_addr = inet_addr(server_addr);
serv_addr.sin_port = htons(portno);

if (connect(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
error("ERROR connecting");

printf("Please enter the message: ");
bzero(buffer,256);
fgets(buffer,255,stdin);
n = write(sockfd,buffer,strlen(buffer));
if (n < 0)
error("ERROR writing to socket");
bzero(buffer,256);
n = read(sockfd,buffer,255);
if (n < 0)
error("ERROR reading from socket");

printf("%s\n",buffer);
close(sockfd);

return 0;
}

(2) Server.cpp

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

void error(const char *msg)
{
perror(msg);
exit(1);
}

int main(int argc, char *argv[])
{
int sockfd, newsockfd, portno;
socklen_t clilen;
char buffer[256];
struct sockaddr_in serv_addr, cli_addr;
int n;
if (argc < 2) {
fprintf(stderr,"ERROR, no port provided\n");
exit(1);
}

sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
error("ERROR opening socket");

bzero((char *) &serv_addr, sizeof(serv_addr));
portno = atoi(argv[1]);

serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
serv_addr.sin_port = htons(portno);

if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
error("ERROR on binding");

listen(sockfd,5);
clilen = sizeof(cli_addr);
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);

if (newsockfd < 0)
error("ERROR on accept");
bzero(buffer,256);

n = read(newsockfd,buffer,255);
if (n < 0)
error("ERROR reading from socket");

printf("Here is the message: %s\n",buffer);
n = write(newsockfd,"I got your message",18);

if (n < 0)
error("ERROR writing to socket");

printf("Here is the message: %s\n",buffer);
n = write(newsockfd,"I got your message",18);

if (n < 0)
error("ERROR writing to socket");

close(newsockfd);
close(sockfd);

return 0;
}