TutThreadCreateVa

Name

TutThreadCreateVa — create a thread (va_list version)

Synopsis

T_THREAD TutThreadCreateVa(thread_func, thread_arg, var_arg_list) 
T_THREAD_FUNC thread_func; 
T_PTR thread_arg; 
va_list var_arg_list;

Arguments

thread_func — function to call from the new thread

thread_arg — argument to pass to thread_func

var_arg_list — argument list

Return Values

Thread handle if successful, T_INVALID_THREAD otherwise.

Diagnostics

If TutThreadCreateVa fails, it returns T_INVALID_THREAD and sets the global SmartSockets error number to one of:

T_ERR_NULL_PTR — thread_func was NULL

T_ERR_OS — an operating system error has occurred. Call the function TutErrNumGetOs to obtain the related OS error value.

T_ERR_TYPE_MISMATCH — the platform does not support threads

Description

TutThreadCreateVa is the non-varargs version of TutThreadCreate. (TutThreadCreate actually calls TutThreadCreateVa.) TutThreadCreateVa can be used to implement a varargs function.

In the C language, a varargs function (one that takes a variable number of arguments) cannot call another varargs function with the original arguments. A varargs function usually calls a helper function that takes a fixed number of arguments, with the last argument usually of type va_list. TutThreadCreateVa is TutThreadCreate’s helper function.

Caution

Threads created by TutThreadCreate or TutThreadCreateVa should always be exited with a call to TutThreadExit or by returning from thread_func, which implicitly calls TutThreadExit for the thread.

Examples

This example implements a minimal replacement for TutThreadCreate (primarily omitting error checking):

T_THREAD my_thread_create(T_THREAD_FUNC thread_func, 
                  T_PTR thread_arg, ...) 
{ 
  va_list var_arg_list; 
  T_THREAD result; 
 
  va_start(var_arg_list, thread_arg); 
  result = TutThreadCreateVa(thread_func, thread_arg, 
                             var_arg_list); 
  va_end(var_arg_list); 
  return result; 
}