网络编程-线程模型

#include <stdio.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <fcntl.h>
#include <pthread.h>
#include <unistd.h>
#define BUFFER_LENGTH 128
void *routine(void *arg)
{
    int clientfd = *(int *)arg;
    while (1) {
        unsigned char buffer[BUFFER_LENGTH] = {0};
        int ret = recv(clientfd, buffer, BUFFER_LENGTH, 0);
        if (ret == 0) {
            close(clientfd);
            break;
        }
        printf("buffer : %s, ret: %d\n", buffer, ret);
        send(clientfd, buffer, ret, 0);
    }
}
int main()
{
    int listenfd = socket(AF_INET, SOCK_STREAM, 0);
    if (listenfd == -1) return -1;
    struct sockaddr_in servaddr;
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
    servaddr.sin_port = htons(9999);
    if (-1 == bind(listenfd, (struct sockaddr*)&servaddr, sizeof(servaddr)))
    {
        return -2;
    }
#if 0 //nonblock
    int flag = fcntl(listenfd, F_GETFL, 0);
    flag |= O_NONBLOCK;
    fcntl(listenfd, F_SETFL, flag);
#endif
    listen(listenfd, 10);
#if 0
    struct sockaddr_in client;
    socklen_t len = sizeof(client);
    int clientfd = accept(listenfd, (struct sockaddr*)&client, &len);
    printf("clientfd: %d\n", clientfd);
    while(1){
        unsigned char buffer[BUFFER_LENGTH] = {0};
        int ret = recv(clientfd, buffer, BUFFER_LENGTH, 0);
        printf("buffer : %s, ret: %d\n", buffer, ret);
        send(clientfd, buffer, ret, 0);
    }
#else
    while (1) {
        struct sockaddr_in client;
        socklen_t len = sizeof(client);
        int clientfd = accept(listenfd, (struct sockaddr*)&client, &len);
        pthread_t threadid;
        pthread_create(&threadid, NULL, routine, &clientfd);
    }
#endif
    return 0;
}