Function llg_matcher_get_error 

#[unsafe(no_mangle)]
pub extern "C" fn llg_matcher_get_error(
    matcher: &mut LlgMatcher,
) -> *const i8

Get the error message from the matcher or null if there is no error. After it returns a non-null value, it will always return it until the matcher is freed using llg_free_matcher() (at which point the pointer will be invalid).

Safety

This function should only be called from C code.