receive_environ
NAME
receive_environ() - called when interactive receives environment options
via telnet negotation.
SYNOPSIS
void receive_environ( string var, string value);
DESCRIPTION
During telnet negotiations, if remote party sends over environment options
defined according to https://tools.ietf.org/html/rfc1572, the user object
will receive this callback to process it.
The user object will be called once for each variable received.