Tutorials needed.

i need some tutorials for multi threading in c++ googled for it but ain't got any good one.. can any one who has is share it..
Threads are not in the standard library (yet), so you need to get some library for this. There are many options. Have you picked one already?
closed account (zwA4jE8b)
Here is an example I found a bit ago. I don't remember where so I do not have a link for you.

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/*  file Main.cpp
 *
 *  This program is an adaptation of the code Rex Jaeschke showed in
 *  Listing 4 of his Nov 2005 C/C++ User's Journal article entitled
 *  "C++/CLI Threading: Part II".  I changed it from C++/CLI (managed)
 *  code to standard C++. 
 *
 *  One hassle is the fact that C++ must employ a free (C) function
 *  or a static class member function as the thread entry function.
 *
 *  This program must be compiled with a multi-threaded C run-time
 *  (/MT for LIBCMT.LIB or /MTd for LIBCMTD.LIB).
 *
 *                                      John Kopplin  7/2006
 */

#include <stdio.h>
#include <windows.h>          // for HANDLE
#include <process.h>          // for _beginthread()
#include <iostream>

static bool interlocked = false;    // change this to fix the problem

const int maxCount = 100000000;
static LONG value = 0;              // under Windows Server 2003 you
                                    // could use LONGLONG here

unsigned __stdcall TMain(void* arg) 
{
    if ( interlocked )
    {
      for ( int i = 1; i <= maxCount; i++ )
      {
        InterlockedIncrement(&value); // under Windows Server 2003 you
                                      // could use InterlockedIncrement64() here
      }
    }
    else
    {
      for ( int i = 1; i <= maxCount; i++ )
      {
        ++value;
		std::cout << value << " ";
      }
    }

    return 3;  // thread exit code
}


int main()
{
    // In this program we create 3 threads and request that their
    // entry-point-function be the TMain() function which is a
    // free (C) function and hence causes no problems for
    // _beginthreadex()

    
    HANDLE   hth1;
    unsigned  uiThread1ID;

    hth1 = (HANDLE)_beginthreadex( NULL,         // security
                                   0,            // stack size
                                   TMain,        // entry-point-function
                                   NULL,         // arg list
                                   CREATE_SUSPENDED,  // so we can later call ResumeThread()
                                   &uiThread1ID );

    if ( hth1 == 0 )
        printf("Failed to create thread 1\n");

    DWORD   dwExitCode;

    GetExitCodeThread( hth1, &dwExitCode );  // should be STILL_ACTIVE = 0x00000103 = 259
    printf( "initial thread 1 exit code = %u\n", dwExitCode );

    HANDLE   hth2;
    unsigned  uiThread2ID;

    hth2 = (HANDLE)_beginthreadex( NULL,         // security
                                   0,            // stack size
                                   TMain,        // entry-point-function
                                   NULL,         // arg list
                                   CREATE_SUSPENDED,  // so we can later call ResumeThread()
                                   &uiThread2ID );

    if ( hth2 == 0 )
        printf("Failed to create thread 2\n");

    GetExitCodeThread( hth2, &dwExitCode );  // should be STILL_ACTIVE = 0x00000103 = 259
    printf( "initial thread 2 exit code = %u\n", dwExitCode );

    HANDLE   hth3;
    unsigned  uiThread3ID;

    hth3 = (HANDLE)_beginthreadex( NULL,         // security
                                   0,            // stack size
                                   TMain,        // entry-point-function
                                   NULL,         // arg list
                                   CREATE_SUSPENDED,  // so we can later call ResumeThread()
                                   &uiThread3ID );

    if ( hth3 == 0 )
        printf("Failed to create thread 3\n");

    GetExitCodeThread( hth3, &dwExitCode );  // should be STILL_ACTIVE = 0x00000103 = 259
    printf( "initial thread 3 exit code = %u\n", dwExitCode );

    // If we hadn't specified CREATE_SUSPENDED in the call to _beginthreadex()
    // we wouldn't now need to call ResumeThread().

    ResumeThread( hth1 );   // Jaeschke's   // t1->Start();
    ResumeThread( hth2 );   // Jaeschke's   // t2->Start();
    ResumeThread( hth3 );   // Jaeschke's   // t3->Start();

    // In C++ the process terminates when the primary thread exits
    // and when the process terminates all its threads are then terminated.
    // Hence if you comment out the following waits, the non-primary
    // threads will never get a chance to run.

    WaitForSingleObject( hth1, INFINITE );  // Jaeschke's t1->Join()
    WaitForSingleObject( hth2, INFINITE );  // Jaeschke's t2->Join()
    WaitForSingleObject( hth3, INFINITE );  // Jaeschke's t3->Join()

    GetExitCodeThread( hth1, &dwExitCode );
    printf( "thread 1 exited with code %u\n", dwExitCode );

    GetExitCodeThread( hth2, &dwExitCode );
    printf( "thread 2 exited with code %u\n", dwExitCode );

    GetExitCodeThread( hth3, &dwExitCode );
    printf( "thread 3 exited with code %u\n", dwExitCode );

    printf( "After %d operations, value = %d\n", 3 * maxCount, value );
                                         // under Windows Server 2003 you
                                         // could use %I64d

    // The handle returned by _beginthreadex() has to be closed
    // by the caller of _beginthreadex().

    CloseHandle( hth1 );
    CloseHandle( hth2 );
    CloseHandle( hth3 );

    printf("Primary thread terminating.\n");
}
closed account (zwA4jE8b)
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/*  file Main.cpp
 *
 *  This program is an adaptation of the code Rex Jaeschke showed in
 *  Listing 1 of his Oct 2005 C/C++ User's Journal article entitled
 *  "C++/CLI Threading: Part I".  I changed it from C++/CLI (managed)
 *  code to standard C++.
 *
 *  One hassle is the fact that C++ must employ a free (C) function
 *  or a static class member function as the thread entry function.
 *
 *  This program must be compiled with a multi-threaded C run-time
 *  (/MT for LIBCMT.LIB in a release build or /MTd for LIBCMTD.LIB
 *  in a debug build).
 *
 *                                      John Kopplin  7/2006
 */


#include <stdio.h>
#include <string>             // for STL string class
#include <windows.h>          // for HANDLE
#include <process.h>          // for _beginthread()

using namespace std;


class ThreadX
{
private:
  int loopStart;
  int loopEnd;
  int dispFrequency;

public:
  string threadName;

  ThreadX( int startValue, int endValue, int frequency )
  {
    loopStart = startValue;
    loopEnd = endValue;
    dispFrequency = frequency;
  }

  // In C++ you must employ a free (C) function or a static
  // class member function as the thread entry-point-function.
  // Furthermore, _beginthreadex() demands that the thread
  // entry function signature take a single (void*) and returned
  // an unsigned.
  static unsigned __stdcall ThreadStaticEntryPoint(void * pThis)
  {
      ThreadX * pthX = (ThreadX*)pThis;   // the tricky cast
      pthX->ThreadEntryPoint();           // now call the true entry-point-function

      // A thread terminates automatically if it completes execution,
      // or it can terminate itself with a call to _endthread().

      return 1;          // the thread exit code
  }

  void ThreadEntryPoint()
  {
     // This is the desired entry-point-function but to get
     // here we have to use a 2 step procedure involving
     // the ThreadStaticEntryPoint() function.

    for (int i = loopStart; i <= loopEnd; ++i)
    {
      if (i % dispFrequency == 0)
      {
          printf( "%s: i = %d\n", threadName.c_str(), i );
      }
    }
    printf( "%s thread terminating\n", threadName.c_str() );
  }
};


int main()
{
    // All processes get a primary thread automatically. This primary
    // thread can generate additional threads.  In this program the
    // primary thread creates 2 additional threads and all 3 threads
    // then run simultaneously without any synchronization.  No data
    // is shared between the threads.

    // We instantiate an object of the ThreadX class. Next we will
    // create a thread and specify that the thread is to begin executing
    // the function ThreadEntryPoint() on object o1. Once started,
    // this thread will execute until that function terminates or
    // until the overall process terminates.

    ThreadX * o1 = new ThreadX( 0, 1000000, 20000 );

    // When developing a multithreaded WIN32-based application with
    // Visual C++, you need to use the CRT thread functions to create
    // any threads that call CRT functions. Hence to create and terminate
    // threads, use _beginthreadex() and _endthreadex() instead of
    // the Win32 APIs CreateThread() and EndThread().

    // The multithread library LIBCMT.LIB includes the _beginthread()
    // and _endthread() functions. The _beginthread() function performs
    // initialization without which many C run-time functions will fail.
    // You must use _beginthread() instead of CreateThread() in C programs
    // built with LIBCMT.LIB if you intend to call C run-time functions.

    // Unlike the thread handle returned by _beginthread(), the thread handle
    // returned by _beginthreadex() can be used with the synchronization APIs.

    HANDLE   hth1;
    unsigned  uiThread1ID;

    hth1 = (HANDLE)_beginthreadex( NULL,         // security
                                   0,            // stack size
                                   ThreadX::ThreadStaticEntryPoint,
                                   o1,           // arg list
                                   CREATE_SUSPENDED,  // so we can later call ResumeThread()
                                   &uiThread1ID );

    if ( hth1 == 0 )
        printf("Failed to create thread 1\n");

    DWORD   dwExitCode;

    GetExitCodeThread( hth1, &dwExitCode );  // should be STILL_ACTIVE = 0x00000103 = 259
    printf( "initial thread 1 exit code = %u\n", dwExitCode );

    // The System::Threading::Thread object in C++/CLI has a "Name" property.
    // To create the equivalent functionality in C++ I added a public data member
    // named threadName.

    o1->threadName = "t1";

    ThreadX * o2 = new ThreadX( -1000000, 0, 20000 );

    HANDLE   hth2;
    unsigned  uiThread2ID;

    hth2 = (HANDLE)_beginthreadex( NULL,         // security
                                   0,            // stack size
                                   ThreadX::ThreadStaticEntryPoint,
                                   o2,           // arg list
                                   CREATE_SUSPENDED,  // so we can later call ResumeThread()
                                   &uiThread2ID );

    if ( hth2 == 0 )
        printf("Failed to create thread 2\n");

    GetExitCodeThread( hth2, &dwExitCode );  // should be STILL_ACTIVE = 0x00000103 = 259
    printf( "initial thread 2 exit code = %u\n", dwExitCode );

    o2->threadName = "t2";

    // If we hadn't specified CREATE_SUSPENDED in the call to _beginthreadex()
    // we wouldn't now need to call ResumeThread().

    ResumeThread( hth1 );   // serves the purpose of Jaeschke's t1->Start()

    ResumeThread( hth2 );

    // In C++/CLI the process continues until the last thread exits.
    // That is, the thread's have independent lifetimes. Hence
    // Jaeschke's original code was designed to show that the primary
    // thread could exit and not influence the other threads.

    // However in C++ the process terminates when the primary thread exits
    // and when the process terminates all its threads are then terminated.
    // Hence if you comment out the following waits, the non-primary
    // threads will never get a chance to run.

    WaitForSingleObject( hth1, INFINITE );
    WaitForSingleObject( hth2, INFINITE );

    GetExitCodeThread( hth1, &dwExitCode );
    printf( "thread 1 exited with code %u\n", dwExitCode );

    GetExitCodeThread( hth2, &dwExitCode );
    printf( "thread 2 exited with code %u\n", dwExitCode );

    // The handle returned by _beginthreadex() has to be closed
    // by the caller of _beginthreadex().

    CloseHandle( hth1 );
    CloseHandle( hth2 );

    delete o1;
    o1 = NULL;

    delete o2;
    o2 = NULL;

    printf("Primary thread terminating.\n");
}
http://lazyfoo.net/SDL_tutorials/lesson33/index.php

So yes, it uses SDL, But honestly, it it the easyest multithreading I have seen :D
can any one suggest what basic knowledge should i have to work in threads..?
Thread safety is one major topic I would recommend. Features like critical section, lock, mutex, semaphore etc are just some of the many mechanism implemented to ensure that. Wrong use can create hard to trace program bug since individual thread codes are executed "simultaneously".
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