Function wcm_last_error 

#[unsafe(no_mangle)]
pub extern "C" fn wcm_last_error() -> *const c_char

Retrieve the last error message from the most recent failed wcm_* call on this thread.

Returns a pointer to a static thread-local C string, or null if no error has occurred. The pointer is valid until the next wcm_* call on the same thread. Do not free this pointer.