在我的上篇博客中已經詳細介紹了socket編程中所需要的函數,在這裏就不過多介紹了,有需要的話可以參考上一篇博客:http://blog.csdn.net/qq_36221862/article/details/73611942
多進程,多線程socket編程與單進程不同的只是服務器端的不同,客戶端是一樣的。
多進程:父進程fork子進程, 子進程退出,但是子進程的子進程仍在運行,變成了孤兒進程,由1號進程回收,父進程不用等待子進程的子進程的退出,它倆是爺孫進程,不用回收子進程。
pid_t id = fork();
if(id < 0)
{
close(new_sock);
}
else if(id == 0) //子進程
{
close(listen_sock); //關閉不必要的文件描述局,不關閉的話,文教描述符表會越來越少,造成資源的浪費
if(fork() > 0)
{
exit(1);
}
else if(id == 0)
{
//服務客戶端
}
else
{
close(new_sock);
}
else
{
close(new_sock);
}
多進程socket編程服務器端代碼:
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h>
#include <string.h>
#include <stdlib.h>
static void usage(const char* proc) //使用說明
{
printf("Usage:%s [local_ip] [local_port]\n", proc);
}
int startup(const char* _ip, int _port) //創建套接字
{
// int sock = socket(AF_INET, SOCK_STREAM , 0);
// if(sock < 0)
/// {
// perror("socket\n");
// exit(2);
// }
**struct sockaddr_in local;
int reuse = 0;
struct sockaddr_in cliaddr, servaddr;
int sock = socket(PF_INET, SOCK_STREAM,0);
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0)
{
perror("setsockopet error\n");
return -1;
}** //避免綁定失敗,在上篇博客也已經解釋過了
local.sin_family = AF_INET;
local.sin_port = htons(_port);
local.sin_addr.s_addr = inet_addr(_ip);
if(bind(sock, (struct sockaddr*)&local, sizeof(local))<0)
{
perror("bind\n");
exit(3);
}
if(listen(sock, 10) < 0)
{
perror("listen\n");
exit(4);
}
return sock;
}
//tcp_server 127.0.0.1 8080
int main(int argc, char* argv[])
{
if(argc != 3)
{
usage(argv[0]);
return 1;
}
int listen_sock = startup(argv[1], atoi(argv[2])); //監聽狀態
struct sockaddr_in client;
socklen_t len = sizeof(client);
struct sockaddr_in cliaddr, servaddr;
while(1)
{
int new_sock = accept(listen_sock, (struct sockaddr*)&client, &len);
if(new_sock < 0)
{
perror("accept\n");
continue; //繼續監聽,直到有新客戶到來
}
//獲取新客戶
printf("get a new client,%s:%d\n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));
//服務新客戶
pid_t id = fork();
if(id < 0)
{
close(new_sock);
}
else if(id == 0) //子進程
{
close(listen_sock);
if(fork() > 0)
{
exit(1);
}
else if(id == 0)
{
while(1)
{
char buf[1024000]; //服務器端先讀再寫
ssize_t s = read(new_sock, buf, sizeof(buf)-1);
if(s > 0)
{
buf[s] = 0;
printf("client: %s\n", buf);
write(new_sock, buf, strlen(buf));
}
else if(s == 0)
{
close(new_sock);
printf("client is quit...\n");
break;
}
else
{
perror("read\n");
close(new_sock);
exit(5);
}
}
}
close(new_sock);
}
else
{
close(new_sock);
}
break;
}
}
多線程:不用關閉多餘的文件描述符表,進程有兩張文件描述符表,而線程只有一張文件描述符表,共享進程的文件描述符表,因此不用關閉多餘的文件描述符表。
查看一個進程有多少個線程:
pthread_t id;
pthread_create(&id, NULL, handlerRequest, (void*)new_sock); //創建線程
pthread_detach(id); //線程分離
多線程socket編程源代碼:
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h>
#include <string.h>-
#include <stdlib.h>
static void usage(const char* proc) //使用說明
{
printf("Usage:%s [local_ip] [local_port]\n", proc);——
}
int startup(const char* _ip, int _port) //創建套接字
{
int sock = socket(AF_INET, SOCK_STREAM , 0);
if(sock < 0)
{
perror("socket\n");
exit(2);
}
struct sockaddr_in local;
local.sin_family = AF_INET;
local.sin_port = htons(_port);
local.sin_addr.s_addr = inet_addr(_ip);
if(bind(sock, (struct sockaddr*)&local, sizeof(local))<0)
{
perror("bind\n");
exit(3);
}
if(listen(sock, 10) < 0)
{
perror("listen\n");
exit(4);
}
return sock;
}
void handlerRequest(void* arg)
{
int new_sock = (int)arg;
while(1)
{
char buf[1024]; //服務器端先讀再寫
ssize_t s = read(new_sock, buf, sizeof(buf)-1);
if(s > 0)
{
buf[s] = 0;
printf("client: %s\n", buf);
write(new_sock, buf, strlen(buf));
}
else if(s == 0)
{
close(new_sock);
printf("client is quit...\n");
break;
}
else
{
perror("read\n");
close(new_sock);
exit(5);
}
}
}
//tcp_server 127.0.0.1 8080
int main(int argc, char* argv[])
{
if(argc != 3)
{
usage(argv[0]);
return 1;
}
int listen_sock = startup(argv[1], atoi(argv[2])); //監聽狀態
struct sockaddr_in client;
socklen_t len = sizeof(client);
while(1)
{
int new_sock = accept(listen_sock, (struct sockaddr*)&client, &len);
if(new_sock < 0)
{
perror("accept\n");
continue; //繼續監聽,直到有新客戶到來
}
//獲取新客戶
printf("get a new client,%s:%d\n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));
//服務新客戶
pthread_t id;
pthread_create(&id, NULL, handlerRequest, (void*)new_sock);
pthread_detach(id); //線程分離
}
}