Given a report of an error, this returns a message explaining the error.

The message will start with the name of the Netica API function which was executing when the error occurred (the one you called, not any that are called internally), followed by a colon, and then a descriptive part. Generally the descriptive part is not just a generic message corresponding to the error number, but rather names the elements involved, and describes what went wrong.

If you need the string to persist, make a copy of the string returned, since its contents may become invalid after further calls to Netica API (such as ClearError_ns or ClearErrors_ns). Do not try to directly modify or free the string returned.