Renamed httplib_join_thread to httplib_pthread_join

doc/api/httplib_pthread_join.md

@@ -0,0 +1,30 @@
+# LibHTTP API Reference
+
+### `httplib_pthread_join( thread, value_ptr );`
+
+### Parameters
+
+| Parameter | Type | Description |
+| :--- | :--- | :--- |
+|**`key`**|`pthread_t`|The ID of the thread to join|
+|**`value_ptr`**|`void *`|Optional pointer to location where the terminating thread stored exit information|
+
+### Return Value
+
+| Type | Description |
+| :--- | :--- |
+|`int`|Integer value with the result of the function|
+
+### Description
+
+The platform independent function `httplib_pthread_join()` suspends the execution of the current thread and waits until another thread specified as parameter has terminated. The function returns **0** when successful and a non zero error code if something goes wrong. On systems which support it, the functionality is implemented as a direct call to `pthread_join()`. Otherwise own code is used which emulates the same functionality.
+
+The parameter `value_ptr` is an optional pointer to a location where an exit pointer of the terminated thread is stored. If this parameter is `NULL` no exit information will be sent back. Please note that the `value_ptr` has only be implemented on systems which use a fall-through to `pthread_join()` but is ignored in other implementations.
+
+### See Also
+
+* [`httplib_pthread_getspecific();`](httplib_pthread_getspecific.md)
+* [`httplib_pthread_key_create();`](httplib_pthread_key_create.md)
+* [`httplib_pthread_key_delete();`](httplib_pthread_key_delete.md)
+* [`httplib_pthread_self();`](httplib_pthread_self.md)
+* [`httplib_pthread_setspecific();`](httplib_pthread_setspecific.md)