HLLAPI provides the ability to connect to a session using a letter A..Z to designate which session. When there were PC environments that limited the number of emulation sessions to 4, this wasn't a big deal, since A..D did the trick.
With a server environment, where 100 or more concurrent sessions may be needed to service the user base, a system using letters is a real problem. While some vendors have implemented the "revolutionary" step of allowing lower-case letters and other characters to drive the maximum "well north of 52" it is more sensible to offer a simple method of utilizing a numeric session request.
In the connect call for HLLAPI, there is a single space provided to indicate the session to connect to. For application developers, it is easy to modify this so that instead of a single character, four characters can be used, and a numeric value passed (as text) instead of a letter.
FlyHLLAPI uses this simple approach and if the first character of the connect request is a numeric digit, finds the next blank and uses the value passed as a numeric session identifier instead of as a letter.
