在服务端用AfxBeginThread开多个线程接收数据，为什么要AfxBeginThread一定在accept()之后呢？

[Luo_Bryant]

//服务器接收数据线程
UINT thread(LPVOID p)
{
//再次启动一个线程，支持多个客户端
// AfxBeginThread(thread,0);
char buff[100];
memset(buff,0,100);
int s=1,msgcount,loop=1,flag=0;
CCSocketDlg *dlg=(CCSocketDlg*)AfxGetApp()->GetMainWnd();
//获得客户端数量
msgcount=dlg->getcount();
if (msgcount==-1)
loop=0;
if(loop)
{
s=1;
// AfxBeginThread(thread,0);
dlg->msgsock[msgcount]=accept(dlg->sock,(sockaddr*)&(dlg->serv),&(dlg->addlen));
AfxBeginThread(thread,0);
if (dlg->msgsock[msgcount]==INVALID_SOCKET)
{
dlg->m_edit.SetWindowText("Error accept");
}
else
{
//启动线程
// AfxBeginThread(thread,0);
dlg->SetForegroundWindow();
dlg->m_list.InsertItem(dlg->count++,"连接成功");
dlg->m_list.InsertItem(dlg->count++,inet_ntoa(dlg->serv.sin_addr));
dlg->m_button.EnableWindow(TRUE);
while(s!=SOCKET_ERROR)
{
//循环接收数据
s=recv(dlg->msgsock[msgcount],buff,100,0);
dlg->SetForegroundWindow();
if (s!=SOCKET_ERROR)
{

dlg->m_list.InsertItem(dlg->count++,buff);
dlg->m_list.Scroll(size);
dlg->sendtoall(dlg->msgsock[msgcount],buff);
}
}
//如果发生错误，发送连接中断消息到客户端
send(dlg->msgsock[msgcount],"Disconnected",100,0);
dlg->m_list.InsertItem(dlg->count++,"luo"); //在服务器端消失信息
dlg->msgsock[msgcount]=NULL;//将该socket设定为NULL
for (int i=0;i<50;i++)
if (dlg->msgsock[i]!=NULL)
flag=1;
if (flag!=1)
dlg->m_button.EnableWindow(FALSE);
closesocket(dlg->msgsock[msgcount]);

}
}
//终止线程
AfxEndThread(0);
return 0;
}





服务端用AfxBeginThread开多个线程接收数据，如果AfxBeginThread()在accept之前，则服务端只能与下一个客户端通信，如果AfxBeginThread()在accept之后，服务端就可以与所有客户端通信了。。。。这是为什么呀？？？求解。。。。

[赵4老师]

《Windows Sockets网络编程》 《Windows核心编程》 以下MyLog.c特供调试多线程程序使用

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef WIN32
    #include <windows.h>
    #include <io.h>
#else
    #include <unistd.h>
    #include <sys/time.h>
    #include <pthread.h>
    #define  CRITICAL_SECTION   pthread_mutex_t
    #define  _vsnprintf         vsnprintf
#endif
//Log{
#define MAXLOGSIZE 20000000
#define MAXLINSIZE 16000
#include <time.h>
#include <sys/timeb.h>
#include <stdarg.h>
char logfilename1[]="MyLog1.log";
char logfilename2[]="MyLog2.log";
static char logstr[MAXLINSIZE+1];
char datestr[16];
char timestr[16];
char mss[4];
CRITICAL_SECTION cs_log;
FILE *flog;
#ifdef WIN32
void Lock(CRITICAL_SECTION *l) {
    EnterCriticalSection(l);
}
void Unlock(CRITICAL_SECTION *l) {
    LeaveCriticalSection(l);
}
#else
void Lock(CRITICAL_SECTION *l) {
    pthread_mutex_lock(l);
}
void Unlock(CRITICAL_SECTION *l) {
    pthread_mutex_unlock(l);
}
#endif
void LogV(const char *pszFmt,va_list argp) {
    struct tm *now;
    struct timeb tb;

    if (NULL==pszFmt||0==pszFmt[0]) return;
    _vsnprintf(logstr,MAXLINSIZE,pszFmt,argp);
    ftime(&tb);
    now=localtime(&tb.time);
    sprintf(datestr,"%04d-%02d-%02d",now->tm_year+1900,now->tm_mon+1,now->tm_mday);
    sprintf(timestr,"%02d:%02d:%02d",now->tm_hour     ,now->tm_min  ,now->tm_sec );
    sprintf(mss,"%03d",tb.millitm);
    printf("%s %s.%s %s",datestr,timestr,mss,logstr);
    flog=fopen(logfilename1,"a");
    if (NULL!=flog) {
        fprintf(flog,"%s %s.%s %s",datestr,timestr,mss,logstr);
        if (ftell(flog)>MAXLOGSIZE) {
            fclose(flog);
            if (rename(logfilename1,logfilename2)) {
                remove(logfilename2);
                rename(logfilename1,logfilename2);
            }
        } else {
            fclose(flog);
        }
    }
}
void Log(const char *pszFmt,...) {
    va_list argp;

    Lock(&cs_log);
    va_start(argp,pszFmt);
    LogV(pszFmt,argp);
    va_end(argp);
    Unlock(&cs_log);
}
//Log}
int main(int argc,char * argv[]) {
    int i;
#ifdef WIN32
    InitializeCriticalSection(&cs_log);
#else
    pthread_mutex_init(&cs_log,NULL);
#endif
    for (i=0;i<10000;i++) {
        Log("This is a Log %04d from FILE:%s LINE:%d\n",i, __FILE__, __LINE__);
    }
#ifdef WIN32
    DeleteCriticalSection(&cs_log);
#else
    pthread_mutex_destroy(&cs_log);
#endif
    return 0;
}