Re: static variables cannot be used in multithread functions?

From:

"Victor Bazarov" <v.Abazarov@comAcast.net>

Newsgroups:

comp.os.ms-windows.programmer.win32,microsoft.public.vc,microsoft.public.vc.language

Date:

Wed, 25 Oct 2006 10:15:59 -0400

Message-ID:

<ehnrj0$qhl$1@news.datemas.de>

BruceWho wrote:

Hi, all

Recently I am playing with multithread programming, and I find that we
cannot use static variables in thread function.The first thread can
start but the second just freeze. Could anybody tell me why?

#include "stdafx.h"
#include "process.h"
#include "windows.h"

void func(void* szName)
{
   // if this static is removed, then everything goes OK.
   static int a = 1;
   while(a<10)
   {
       printf("%s:%d\n", szName, a++);

Add
Sleep(100);

here, see if it makes any difference.

   }
}

int main(int argc, char* argv[])
{
   printf("thread1 starts\n");
_beginthread(func, 0, "t1");
   printf("thread2 starts\n");
   _beginthread(func, 0, "t2");
Sleep(5000);
   return 0;
}

this is the output:

thread1 starts
thread2 starts
t1:1
t1:2
t1:3
t1:4
t1:5
t1:6
t1:7
t1:8
t1:9
Press any key to continue

V
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