Почему приведенный ниже пример кода заставляет один поток выполняться быстрее, чем другой, а мьютекс - нет?
#include <windows.h>
#include <conio.h>
#include <process.h>
#include <iostream>
using namespace std;
typedef struct _THREAD_INFO_ {
COORD coord; // a structure containing x and y coordinates
INT threadNumber; // each thread has it's own number
INT count;
}THREAD_INFO, * PTHREAD_INFO;
void gotoxy(int x, int y);
BOOL g_bRun;
CRITICAL_SECTION g_cs;
unsigned __stdcall ThreadFunc( void* pArguments )
{
PTHREAD_INFO info = (PTHREAD_INFO)pArguments;
while(g_bRun)
{
EnterCriticalSection(&g_cs);
//if(TryEnterCriticalSection(&g_cs))
//{
gotoxy(info->coord.X, info->coord.Y);
cout << "T" << info->threadNumber << ": " << info->count;
info->count++;
LeaveCriticalSection(&g_cs);
//}
}
ExitThread(0);
return 0;
}
int main(void)
{
// OR unsigned int
unsigned int id0, id1; // a place to store the thread ID returned from CreateThread
HANDLE h0, h1; // handles to theads
THREAD_INFO tInfo[2]; // only one of these - not optimal!
g_bRun = TRUE;
ZeroMemory(&tInfo, sizeof(tInfo)); // win32 function - memset(&buffer, 0, sizeof(buffer))
InitializeCriticalSection(&g_cs);
// setup data for the first thread
tInfo[0].threadNumber = 1;
tInfo[0].coord.X = 0;
tInfo[0].coord.Y = 0;
h0 = (HANDLE)_beginthreadex(
NULL, // no security attributes
0, // defaut stack size
&ThreadFunc, // pointer to function
&tInfo[0], // each thread gets its own data to output
0, // 0 for running or CREATE_SUSPENDED
&id0 ); // return thread id - reused here
// setup data for the second thread
tInfo[1].threadNumber = 2;
tInfo[1].coord.X = 15;
tInfo[1].coord.Y = 0;
h1 = (HANDLE)_beginthreadex(
NULL, // no security attributes
0, // defaut stack size
&ThreadFunc, // pointer to function
&tInfo[1], // each thread gets its own data to output
0, // 0 for running or CREATE_SUSPENDED
&id1 ); // return thread id - reused here
_getch();
g_bRun = FALSE;
return 0;
}
void gotoxy(int x, int y) // x=column position and y=row position
{
HANDLE hdl;
COORD coords;
hdl = GetStdHandle(STD_OUTPUT_HANDLE);
coords.X = x;
coords.Y = y;
SetConsoleCursorPosition(hdl, coords);
}