Multi Thread

[Supaflyfrank]

I Just Wanted To Know I Changed Mircosoft MultiThread Program Which Was Written In C To Use C++ Functions So I Can Turn This Whole Program In C++ But The Problem Is That After My Program Creates A Thread It Doesnt Run A Certain Function And I Dont Know What The Problem Is This Program Suppose To Run On The Command Prompt And When You Run It And Hit A It Creates A New Thread Which Then Will Cause A Happy Face To Bounce Around The Screen And If You Hit A Again +1 More Happy Face Will Bounce Around The Screen And It Will Do That Till There Is 32 Happy Faces Bounceing Around The Screen. But I Dont Know Why This Program Isnt Working I Hit A And Nothing Happens Can Some One Please Help Me Thank You In Advance.







// BOUNCE.CPP


/* Bounce - Creates a new thread each time the letter 'a' is typed.
* Each thread bounces a happy face of a different color around the screen.
* All threads are terminated when the letter 'Q' is entered.
*
* This program requires the multithread library. For example, compile
* with the following command line:
* CL /MT BOUNCE.C
*/

#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <conio.h>
#include <process.h>

#define MAX_THREADS 32

/* getrandom returns a random number between min and max, which must be in
* integer range.
*/
#define getrandom( min, max ) ((rand() % (int)(((max) + 1) - (min))) + (min))

int main( void ); /* Thread 1: main */
void KbdFunc( void ); /* Keyboard input, thread dispatch */
void ClearScreen( void ); /* Screen clear */
void ShutDown( void ); /* Program shutdown */
void WriteTitle( int ThreadNum ); /* Display title bar information */

DWORD WINAPI BounceThreadProc( LPVOID lpParameter ); /* Threads 2 to n: display */

HANDLE hConsoleOut; /* Handle to the console */
HANDLE hRunMutex; /* &quot;Keep Running&quot; mutex */
HANDLE hScreenMutex; /* &quot;Screen update&quot; mutex */
int ThreadNr; /* Number of threads started */
CONSOLE_SCREEN_BUFFER_INFO csbiInfo; /* Console information */


int main() /* Thread One */
{
/* Get display screen information & clear the screen.*/
hConsoleOut = GetStdHandle( STD_OUTPUT_HANDLE );
GetConsoleScreenBufferInfo( hConsoleOut, &csbiInfo );
ClearScreen();
WriteTitle( 0 );
/* Create the mutexes and reset thread count. */
hScreenMutex = CreateMutex( NULL, FALSE, NULL ); /* Cleared */
hRunMutex = CreateMutex( NULL, TRUE, NULL ); /* Set */
ThreadNr = 0;

/* Start waiting for keyboard input to dispatch threads or exit. */
KbdFunc();

/* All threads done. Clean up handles. */
CloseHandle( hScreenMutex );
CloseHandle( hRunMutex );
CloseHandle( hConsoleOut );

return 0;
}

void ShutDown( void ) /* Shut down threads */
{
while ( ThreadNr > 0 )
{
/* Tell thread to die and record its death. */
ReleaseMutex( hRunMutex );
ThreadNr--;
}
/* Clean up display when done */
WaitForSingleObject( hScreenMutex, INFINITE );
ClearScreen();
}

void KbdFunc( void ) /* Dispatch and count threads. */
{
int KeyInfo;

do
{
KeyInfo = _getch();
if( tolower( KeyInfo ) == 'a' && ThreadNr < MAX_THREADS )
{
ThreadNr++;
CreateThread(NULL, 0, BounceThreadProc, (LPVOID)ThreadNr, 0, NULL );
WriteTitle( ThreadNr );
}
} while( tolower( KeyInfo ) != 'q' );

ShutDown();
}

DWORD WINAPI BounceThreadProc( LPVOID lpParameter )
{
char MyCell, OldCell;
WORD MyAttrib, OldAttrib;
char BlankCell = 0x20;
COORD Coords, Delta;
COORD Old = {0,0};
DWORD Dummy;

DWORD ThreadNum = (unsigned long)lpParameter;

/* Generate update increments and initial display coordinates. */
srand( ThreadNum * 3 );
Coords.X = getrandom( 0, csbiInfo.dwSize.X - 1 );
Coords.Y = getrandom( 0, csbiInfo.dwSize.Y - 1 );
Delta.X = getrandom( -3, 3 );
Delta.Y = getrandom( -3, 3 );

/* Set up &quot;happy face&quot; & generate color attribute from thread number.*/
if( ThreadNum > 16)
MyCell = 0x01; /* outline face */
else
MyCell = 0x02; /* solid face */
MyAttrib = (unsigned)ThreadNum & 0x0F; /* force black background */

do
{
/* Wait for display to be available, then lock it. */
WaitForSingleObject( hScreenMutex, INFINITE );

/* If we still occupy the old screen position, blank it out. */
ReadConsoleOutputCharacter( hConsoleOut, &OldCell, 1, Old, &Dummy );
ReadConsoleOutputAttribute( hConsoleOut, &OldAttrib, 1, Old, &Dummy );
if (( OldCell == MyCell ) && (OldAttrib == MyAttrib))
WriteConsoleOutputCharacter( hConsoleOut, &BlankCell, 1, Old, &Dummy );

/* Draw new face, then clear screen lock */
WriteConsoleOutputCharacter( hConsoleOut, &MyCell, 1, Coords, &Dummy );
WriteConsoleOutputAttribute( hConsoleOut, &MyAttrib, 1, Coords, &Dummy );
ReleaseMutex( hScreenMutex );

/* Increment the coordinates for next placement of the block. */
Old.X = Coords.X;
Old.Y = Coords.Y;
Coords.X += Delta.X;
Coords.Y += Delta.Y;

/* If we are about to go off the screen, reverse direction */
if( Coords.X < 0 || Coords.X >= csbiInfo.dwSize.X )
{
Delta.X = -Delta.X;
Beep( 400, 50 );
}
if( Coords.Y < 0 || Coords.Y > csbiInfo.dwSize.Y )
{
Delta.Y = -Delta.Y;
Beep( 600, 50 );
}
}
/* Repeat while RunMutex is still taken. */
while ( WaitForSingleObject( hRunMutex, 75L ) == WAIT_TIMEOUT );

// not sure if we need this??
ExitThread(0);

return 0;
}

void WriteTitle( int ThreadNum )
{
char NThreadMsg[80];

sprintf( NThreadMsg, &quot;Threads running: %02d. Press 'A' to start a thread,'Q' to quit.&quot;, ThreadNum );
SetConsoleTitle( NThreadMsg );
}

void ClearScreen( void )
{
DWORD dummy;
COORD Home = { 0, 0 };
FillConsoleOutputCharacter( hConsoleOut, ' ', csbiInfo.dwSize.X * csbiInfo.dwSize.Y, Home, &dummy );
}

 

[Cheiron]

I don't know if this will be good news or bad news, but after finding nothing wrong with a quick desk check, I ran your program on my machine and it ran fine. After pressing &quot;a&quot; a bunch of times I had a zoo of multi-colored happy faces bouncing around in the console. I pressed &quot;q&quot; and all the threads exited cleanly.

This has nothing to do with the problem, but the answer to the question in the code about &quot;do I need ExitThread&quot; is, &quot;no&quot;. You don't need exit thread. It is fine just to exit from the thread by returning zero. (Your program works either way.)

 

[Cagliostro]

use debugger to see what is exactly inside.

Ion Filipski

ICQ: 95034075
AIM: IonFilipski
filipski@excite.com

 

[amgln]

if your OS is win me/95/98 CreateThread function must not have the last argument as NULL.