multithreaded using _beginthreadex passing parameters - multithreading

Question

Visual Studio C++ 2008
I am using threads. However, I have this warnings and not sure what I am doing wrong.
1. unsigned int (__stdcall *)(void *) differs in levels of indirection from 'void *(__stdcall *)(void *)'
2. _beginthreadex different types for formal and actual parameters 3
/* Function prototype */
void* WINAPI get_info(void *arg_list)
DWORD thread_hd;
DWORD thread_id;
/* Value to pass to the function */
int th_sock_desc = 0;
/* Create thread */
thread_hd = _beginthreadex(NULL, 0, get_info, (void*) th_sock_desc, 0, &thread_id);
if(thread_hd == 0)
{
/* Failed to create thread */
fprintf(stderr, "[ %s ] [ %s ] [ %d ]\n", strerror(errno), __func__, __LINE__);
return 1;
}

Answer 1

the Thread function that you pass to _beginthreadex has a different prototype than the one you pass to _beginthread
uintptr_t _beginthread(
void( *start_address )( void * ),
unsigned stack_size,
void *arglist
);
uintptr_t _beginthreadex(
void *security,
unsigned stack_size,
unsigned ( *start_address )( void * ),
void *arglist,
unsigned initflag,
unsigned *thrdaddr
);
It's the same as what CreateThread expects,
DWORD WINAPI ThreadProc(
__in LPVOID lpParameter
);
So you need to change the function signature of your thread proc to
unsigned WINAPI get_info(void *arg_list)
remove WINAPI and change the return type.
Edit :
WINAPI is actually needed, the docs show the wrong prototype for _beginthredex, but they explicitly state that __stdcall is needed. Your problem is just the return type. Also, the error message, says that __stdcall is expected, so that settles it.