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Programming: Windows Threading Vs Linux Threading

In this article, I'm trying to show some differences between Windows and Linux thread creation and their respective usage.

Creating Threads:

1.
    a. In Windows: CreateThread() API is used to create a thread to execute within the virtual address space of the calling process.
    b. In Linux: pthread_create() function creates a thread.

    Function Signature:
    // Windows
    HANDLE WINAPI CreateThread(
          _In_opt_   LPSECURITY_ATTRIBUTES lpThreadAttributes,
          _In_       SIZE_T dwStackSize,
          _In_       LPTHREAD_START_ROUTINE lpStartAddress,
          _In_opt_   LPVOID lpParameter,
          _In_       DWORD dwCreationFlags,
          _Out_opt_  LPDWORD lpThreadId
    );

    Function Signature:
    // Linux
    int pthread_create(pthread_t *thread, const pthread_attr_t *attr,
         void *(*start_routine)(void *), void *arg);

    In Windows: We can pass stack size in bytes if required to the same CreateThread() API.
    In Linux:  The stack size is set in the pthread attributes object; that is, the parameter attr of type pthread_attr_t is passed to the library call pthread_create().
        This object needs to be initialized by the call pthread_attr_init() before any attributes are set.
        The attribute object is destroyed using the call pthread_attr_destroy().
        The stack size is set using the call pthread_attr_setstacksize(): int pthread_attr_setstacksize(pthread_attr_t *threadAttr, int stack_size);

    This article uses default thread attributes to create threads on Windows and Linux.
    In Windows: Used WaitForMultipleObjects() API to force main() to wait until all threads execution are done.
    In Linux: Used pthread_join() to achieve the same.

    The following code snippets do the same stuff on Windows and Linux but there are some differences from a programming point of view.
    Code Windows:
    =============
    #include < windows.h >
    #include < stdio.h >
    #define MAX_THREADS 2

    struct MyData
    {
        char name[20];
        char thread[20];
    };

    DWORD WINAPI MyThreadFunction( LPVOID lpParam );

    int _tmain(int argc, _TCHAR* argv[])
    {
        HANDLE hThread[2] = {NULL};
   
        DWORD   dwThreadId;
        struct MyData mData1;
        struct MyData mData2;

        strcpy(mData1.name, "Testing - 1");
        strcpy(mData1.thread, "Thread - 1");

        strcpy(mData2.name, "Testing - 2");
        strcpy(mData2.thread, "Thread - 2");

        hThread[0] = CreateThread(
            NULL,                // Default Security Attributes
            0,                    // Use Default Stack size
            MyThreadFunction,    // Thread function name
            &mData1,            // Argument to thread function
            0,                    // Use default creation flags
            &dwThreadId
            );

        if(NULL == hThread[0])
        {
            printf("CreateThread failed for Thread 1\n");
        }
   
        hThread[1] = CreateThread(
            NULL,                // Default Security Attributes
            0,                // Use Default Stack size
            MyThreadFunction,        // Thread function name
            &mData2,            // Argument to thread function
            0,                    // Use default creation flags
            &dwThreadId
        );

        if(NULL == hThread[1])
        {
            printf("CreateThread failed for Thread 2\n");
        }

        // Wait until all threads have terminated.
        WaitForMultipleObjects(MAX_THREADS, hThread, TRUE, INFINITE);

        CloseHandle(hThread[0]);
        CloseHandle(hThread[1]);
   
        return 0;
    }

    DWORD WINAPI MyThreadFunction( LPVOID lpParam )
    {
        struct MyData *p = (struct MyData *)lpParam;
        printf("Name: %s\n", p->name);
        printf("Thread: %s\n", p->thread);
        printf("+++++++++++++++++++++++++++++\n");

        return 0;
    }   

    Code Linux:
    =============
    #include < pthread.h >
    #include < stdio.h >
    #include < string.h >

    struct mystruct
    {
        char name[20];
        char thread[20];
    };

    void *Print_Details(void *param)
    {
        /*Cast the pointer to right type */
        struct mystruct* p = (struct mystruct*) param;

        printf("Name: %s\n", p->name);
        printf("Thread: %s\n", p->thread);
        printf("+++++++++++++++++++\n");   

        return NULL;
    }

    /* Main program */

    int main()
    {
        pthread_t thread1;
        pthread_t thread2;

        struct mystruct args1;
        struct mystruct args2;

        /* Create new thread */
        strcpy(args1.name, "Testing - 1");
        strcpy(args1.thread, "Thread - 1");
        pthread_create(&thread1, NULL, &Print_Details, &args1);

        /* Create another new thread */
        strcpy(args2.name, "Testing - 2");
        strcpy(args2.thread, "Thread - 2");
        pthread_create(&thread2, NULL, &Print_Details, &args2);

        /* Ensure the First thread has finished */
        pthread_join(thread1, NULL);
   
        /* Ensure the second thread has finished */
        pthread_join(thread2, NULL);

        /* Now safe to return main */
        return 0;
    }

Reference Windows: http://msdn.microsoft.com/en-us/library/ms682453%28VS.85%29.aspx
Reference Linux: http://publib.boulder.ibm.com/infocenter/iseries/v5r4/index.jsp?topic=%2Fapis%2Fusers_14.htm
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