多线程并发回声服务器的实现（Linux版）

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <pthread.h>

#define BUF_SIZE 100
#define MAX_CLNT 256

void *handle_clnt(void *arg);
void send_msg(char *msg, int len);
void error_handing(char *msg);

int clnt_cnt = 0;
int clnt_socks[MAX_CLNT];
pthread_mutex_t mutx;

int main(int argc, char *argv[])
{
    int serv_sock, clnt_sock;
    struct sockaddr_in serv_adr, clnt_adr;
    int clnt_adr_sz;
    pthread_t t_id;
    if(argc != 2) {
        printf("Usage : %s <port>", argv[0]);
        exit(1);
    }

    pthread_mutex_init(&mutx, NULL);
    serv_sock = socket(AF_INET, SOCK_STREAM, 0);

    memset(&serv_adr, 0, sizeof(serv_adr));
    serv_adr.sin_family = PF_INET;
    serv_adr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_adr.sin_port = htons(atoi(argv[1]));

    if(bind(serv_sock, (struct sockaddr *)&serv_adr, sizeof(serv_adr)) == -1)
        error_handing("bind() error");
    if(listen(serv_sock, 5) == -1)
        error_handing("listen() error");

    while(1)
    {
        clnt_adr_sz = sizeof(clnt_adr);
        clnt_sock = accept(serv_sock, (struct sockaddr *)&serv_adr, &clnt_adr_sz);

        pthread_mutex_lock(&mutx);
        clnt_socks[clnt_cnt ++] = clnt_sock;
        pthread_mutex_unlock(&mutx);

        pthread_create(&t_id,NULL,handle_clnt, (void *)&clnt_sock);
        pthread_detach(&t_id);
        printf("Connected client IP: %s 
", inet_ntoa(clnt_adr.sin_addr));
    }
    close(serv_sock);
    return 0;
}

void *handle_clnt(void *arg)
{
    int clnt_sock = *((int *)arg);
    int str_len = 0, i;
    char msg[BUF_SIZE];

    while((str_len = read(clnt_sock, msg, sizeof(msg))) != 0)
        send_msg(msg, str_len);

    pthread_mutex_lock(&mutx);
    for(i = 0; i < clnt_cnt; i ++)
    {
        if(clnt_sock == clnt_socks[i])
        {
            while(i ++ < clnt_cnt - 1)
                clnt_socks[i] = clnt_socks[i + 1];
            break;
        }
    }
    clnt_cnt --;
    pthread_mutex_unlock(&mutx);
    close(clnt_sock);
    return NULL;
}

void send_msg(char *msg, int len)
{
    int i;
    pthread_mutex_lock(&mutx);
    for(i = 0; i < clnt_cnt; i ++)
        write(clnt_socks[i], msg, len);
    pthread_mutex_unlock(&mutx);
}

void error_handing(char *msg)
{
    fputs(msg, stderr);
    fputc('
', stderr);
    exit(1);
}

　　多线程并发回声服务器代码（linux版）