Searches DNS for MX records corresponding to hostname. Returns TRUE if any records are found; returns FALSE if no records were found or if an error occurred.
A list of the MX records found is placed into the array mxhosts. If the weight array is given, it will be filled with the weight information gathered.
Note: This function is not implemented on Windows platforms.
See also checkdnsrr(), gethostbyname(), gethostbynamel(), gethostbyaddr(), and the named(8) manual page.