网络编程与多线程 编译参数

编译时要链接操作系统的pthread库

g++ -g socket01.cpp -std=c++11 -pthread

不加-pthread的话，出现下面的错误：

terminate called after throwing an instance of 'std::system_error'        
  what():  Enable multithreading to use std::thread: Operation not permit
ted

例子：

#include <sys/types.h>//socket()                                          
#include <sys/socket.h>//socket()                                         
#include <unistd.h>//close()                                              
#include <arpa/inet.h>//结构体sockaddr_in                                 
#include <string.h>//函数strstr                                           
#include <iostream>
#include <thread>

using namespace std;

class TcpThread{
public:
  void main(){
    cout << "in tread main !!!!!!!!!!!!!!" << endl;
    char buf[1024] = {0};
    while(true){
      //虽然指定了接收数据的大小为sizeof(buf) - 1，                       
      //但实际能接收到多少，是不一定的,                                   
      //len1是实际接到的数据的大小                                        
      int len1 = recv(client, buf, sizeof(buf) - 1, 0);
      cout << "recv len is : " << len1 << endl;
      if(len1 <= 0) break;
      buf[len1] = '';
      if(strstr(buf, "quit") != NULL){
        char re[] = "quit sucessn";
        send(client, re, strlen(re) + 1, 0);
        break;
      }
      //给客户端发送信息，如果发送的数据大，会自动被切割车成很多小块      
      //分多次发出去                                                      
      //虽然指定了发送数据的大小为3，                                     
      //但实际能发出去多少，是不一定的,                                   
      //sendlen是实际发送出去的数据的大小                                 
      int sendlen = send(client, "OKn", 4, 0);
      cout << "send len is : " << sendlen << endl;
      cout << "recv is : " << buf << endl;

    }
    close(client);
    delete this;
  }
  int client = 0;
};
int main(int argc, char* argv[]){

  unsigned short port = 8080;
  int sock = socket(AF_INET,SOCK_STREAM,0);
  if(argc > 1){
    port = atoi(argv[1]);
  }
  sockaddr_in saddr;
  saddr.sin_family = AF_INET;
  //把本地字节序，转成网络字节序                                          
  saddr.sin_port = htons(port);
  saddr.sin_addr.s_addr = htonl(0);
  if(bind(sock,(sockaddr*)&saddr, sizeof(saddr)) != 0){
    cout << "bind failed" << endl;
    return -2;
  }
  cout << "success:" << port << endl;
  listen(sock, 10);
  while(true){
    sockaddr_in caddr;
    socklen_t len = sizeof(caddr);
    //根据原来的sock，生成一个新的socket，叫clinet                        
    //原来的sock是专门用来建立连接的                                      
    int client = accept(sock, (sockaddr*)&caddr, &len);
    if(client <= 0)break;
    cout << client << endl;
    char *ip = inet_ntoa(caddr.sin_addr);
    //把网络字节序，转成本地字节序                                        
    unsigned short cport = ntohs(caddr.sin_port);
    cout << "clinet ip is " << ip << " port is " << cport << endl;

    TcpThread* th = new TcpThread();
    th->client = client;

    //开启多线程                                                          
    std::thread sth(&TcpThread::main, th);
    //让子线程脱离父线程的监管                               
    sth.detach();
  }
  close(sock);
}

github源代码