與多進程相同,採用多線程可以實現併發服務器,並且由於線程的系統開銷小,切換時間短,對於需要處理大量客戶的服務器而言其具有更大的優勢,實現多線程併發服務器的基本流程是:當建立連接以後,服務器調用pthread_create()函數產生新的線程,由新的線程來處理客戶端的請求,同時主線程等待另一個客戶的連接請求,其中的典型的模板如下:
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<unistd.h>
#include<stdlib.h>
#include<pthread.h>
/***********function to be executed by the new thread**************/
void *start_routine((void *)arg);
int main()
{
int listenf,connfd;
pthread_t tid;
type arg;
struct sockaddr_in servaddr,cliaddr;
/****************create the tcp sock *******************/
listenfd=socket(AF_INET,SOCK_STREAM,0);
bzero(&servaddr,sizeof(servaddr));
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
servaddr.sin_port=htons(1032);
/******************************bind socket to address****************************/
bind(listenfd,(struct sockaddr *)&servaddr,sizeof(servaddr));
listen(listenfd,5);
while(1)
{
/********************accept the connection****************************/
clilen=sizeof(cliaddr);
connfd=accept(listenfd,(struct sockaddr *)&cliaddr,&clilen);
/*************************create child to service client***************************************/
/********************************put the parameters to the arg*******************************************/
if(pthread_create(&tid,NULL,start_routine,(void *)arg))
{
//handle exception
................
eixt(0);
}
}//總之就是要實現多線程的功能就是把線程的申明放在建立連接之後
以下是實現 一次啓動Server端和Client端後,首先由Server端發‘1’給Client端,Client端將接收到的數據加1後,發該數據給Server端,Server端再將數據加1後發給Client端,依次類推。直到Server端收到數據20,Client收到19時,兩方中斷收發功能的服務器和客戶端的程序實現:(應用多線程網絡編程實現)
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# include <netdb.h>
# include <stdio.h>
#include<pthread.h>
void deal(int connfd1);
int main(int argc,char **argv)
{
int listenfd,connfd;
struct sockaddr_in servaddr,cliaddr;
//char recvline[1024];
//char send[1024];
pthread_t tid;//用來申請作爲線程用的語句
socklen_t clilen;
int n=0;
listenfd=socket(AF_INET,SOCK_STREAM,0);
bzero(&servaddr,sizeof(servaddr));
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
servaddr.sin_port=htons(1032);
bind(listenfd,(struct sockaddr *)&servaddr,sizeof(servaddr));
listen(listenfd,5);
for(;;)
{
clilen=sizeof(cliaddr);
connfd=accept(listenfd,(struct sockaddr *)&cliaddr,&clilen);
/****************************create thread*******************************/
if(pthread_create(&tid,NULL,deal,(void *)connfd))
{
printf("the create thread error");
exit(0);
}
}
close(listenfd);
return 0;
}
/****************the function of deal()***********************/
void deal(int connfd)
{
char recvline[1024];
char send[1024];
int n=0;
while(n<20)
{
n=n+1;
printf("the server send is:%d\n",n);
sprintf(send,"%d",n);
if(write(connfd,send,strlen(send))==0)
{
printf("the write error!");
exit(1);
}
/***********read the information****************/
if(read(connfd,recvline,1024)==0)
{
printf("the read error!");
exit(1);
}
n=atoi(recvline);
printf("the server accept is:%d\n",n);
}
close(connfd);
pthread_exit(NULL);
}
客戶端的實現如下:
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# include <netdb.h>
# include <stdio.h>
#include<stdlib.h>
int main(int argc,char **argv)
{
int sockfd;
char recvline[100];
char sendline[100];
struct sockaddr_in servaddr;
struct hostcnt *h;
int n=0;
if(argc!=2)
{
printf("usage:a.out <ipaddress>");
}
if((sockfd=socket(AF_INET,SOCK_STREAM,0))<0)
{
printf("socket error!");
}
bzero(&servaddr,sizeof(servaddr));
servaddr.sin_family=AF_INET;
servaddr.sin_port=htons(1032);//把數值轉換成網絡字節值
if((inet_pton(AF_INET,argv[1],&(servaddr.sin_addr)))<0)
{//把字符串型的形式轉換成地址的格式
printf("address error!\n");
}
//建立與服務器的鏈接
if(connect(sockfd,(struct sockaddr *)&servaddr,sizeof(servaddr))<0)//本語句中之所以可以用servaddr是因爲,客戶端與服務器端的端口號和ip地址是一樣的
{//一般情況下是通過指定servaddr來指定要鏈接的服務器的ip地址以及服務器的端口號來實現和服務器進行鏈接
printf("connect error!\n");
}
while(n<19)
{
if(read(sockfd,recvline,1024)==0)
{
printf("read error!");
exit(0);
}
n=atoi(recvline);
printf("the client accept is:%d\n",n);
sprintf(sendline,"%d",(n+1));
write(sockfd,sendline,strlen(sendline));
printf("the client send is:%d\n",(n+1));
}
exit(0);
}