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    CreateTask -- Create task with given name, priority, stacksize

    task = CreateTask(name,pri,initPC,stackSize)

    struct Task *CreateTask(STRPTR,LONG,funcEntry,ULONG);

    This function simplifies program creation of sub-tasks by
    dynamically allocating and initializing required structures
    and stack space, and adding the task to Exec's task list
    with the given name and priority. A tc_MemEntry list is provided
    so that all stack and structure memory allocated by CreateTask()
    is automatically deallocated when the task is removed.

    An Exec task may not call dos.library functions or any function
    which might cause the loading of a disk-resident library, device,
    or file (since such functions are indirectly calls to dos.library).
    Only AmigaDOS Processes may call AmigaDOS; see the
    dos.library/CreateProc() or the dos.library/CreateNewProc()
    functions for more information.

    If other tasks or processes will need to find this task by name,
    provide a complex and unique name to avoid conflicts.

    If your compiler provides automatic insertion of stack-checking
    code, you may need to disable this feature when compiling sub-task
    code since the stack for the subtask is at a dynamically allocated
    location.  If your compiler requires 68000 registers to contain
    particular values for base relative addressing, you may need to
    save these registers from your main process, and restore them
    in your initial subtask code.

    The function entry initPC is generally provided as follows:

    In C:
    extern void functionName();
    char *tname = "unique name";
    task = CreateTask(tname, 0L, functionName, 4000L);

    In assembler:
            PEA     startLabel

    name - a null-terminated name string
    pri - an Exec task priority between -128 and 127, normally 0
    funcEntry - the address of the first executable instruction
                of the subtask code
    stackSize - size in bytes of stack for the subtask. Don't cut it
                too close - system function stack usage may change.

    task - a pointer to the newly created task, or NULL if there was not
           enough memory.

    Under exec.library V37 or beyond, the AddTask() function used
    internally by CreateTask() can fail whereas it couldn't fail in
    previous versions of Exec. Prior to amiga.lib V37.14, this function
    did not check for failure of AddTask() and thus might return a
    pointer to a task structure even though the task was not actually
    added to the system.

    DeleteTask(), exec/FindTask()

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