Error codes are unsigned 32-bit values which are private to each
calling thread. You should call the LlmGetLastError function
immediately when a function's return value indicates that an error
has occurred. Functions set this value by calling LlmSetLastError.
The Return Value section of each reference page notes the conditions
under which a function sets the last error code.
Most functions will set the last error code value when they fail;
a few functions set it when they succeed. Function failure is
typically indicated by a return value such as FALSE, NULL,
INVALID_CLIENT or LLM_ERROR. Those functions which call
LlmSetLastError when they succeed are noted on the function
reference page.
This function should only be called when a preceding function indicates
failure. Calling this function after a successful call may return a
value unrelated to the most recent operation.