This extension provides PHP language bindings for the functions and constants exposed by the » getdns API and library. getdns is a modern, asynchronous DNS API that simplifies access to advanced DNS features, including DNSSEC. This extension is built on top of the getdns implementation developed as a joint project between » Verisign Labs and » NLnet Labs.
Additional information about the API and the functions that implement it can be found on the » getdns web site.
NOTE: THIS IS A BETA RELEASE! This implementation is licensed under the New BSD License (BSD-new).
Dictionaries and lists: the getdns API and library organize information using data structures called "dictionaries" and "lists". Dictionaries are similar to associative arrays in PHP. Elements are identified by a character string and can be set and retrieved using the string as a reference. Lists are similar to indexed arrays. Elements are identified by an integer key and can be set and retrieved using the integer index as a reference. This extension uses an integer reference that represents the memory address for dictionaries and lists created by the getdns library. Values can be set or retrieved using functions provided by the getdns library. Dictionaries and lists can also be converted to PHP arrays (and vice-versa) using a set of non-API functions provided by this extension.
Transaction identifiers: the getdns library uses 64-bit unsigned integers to represent the transaction identifiers associated with asynchronous operations. PHP 5.x doesn't provide native support for 64-bit unsigned integers, so this extension represents transaction identifier values as 16-character hexadecimal strings that represent the 64-bit identifier value.