netsnmp_handler(3snmp) on Linux
The text d593c4f8c415, as Debian 7 (Wheezy), Debian 6.0 (Squeeze) shipped it. The page shows this text now.
The basic theory goes something like this: In the past, with the original mib module api (which derived from the original CMU SNMP code) the underlying mib modules were passed very little information (only the truly most basic information about a request).