The source code for the WinSock communication interface used by NMT is available online.

NI Mainframe Service:
·  A NT Service which can be used to test and evaluate Telnet 3270 and 5250 clients.
·  It can be installed and run from any Windows NT Server/WS.
·  At startup it will open three listen ports (default 5021, 5022 and 5023).
·  On each port a set of difference 3270/5250 screen images will be returned.
·  Listen port numbers can be set in registry at System \ CurrentControlSet \ Services \ NI_MFS.
·  The first port (5021) is a "slow" replay mode, with a delay of 1.5 second.
·  The next port (5022) is a "contiguous loop" port. This is done with an insertion of a query at the end of each screen image.
·  This port connection can be used for performance and stability evaluating.
·  The last port (5023) is a "normal" replay mode connection.
·  The event log will be updated when a new connection has been established and when it is disconnected.
·  The following information will be added if a loop connection has been disconnected:
LoopCount msConnected msConnected/LoopCount

Installation:
·  Copy ni_mfs.exe to your system directory (\WINNT\SYTEM32) and type: ni_mfs.exe -install
·  Than it can be started from the Control Panel or with the command: net start ni_mfs
·  And it can be removed with the command: ni_mfs.exe -remove

Download NI Mainframe Service - 80 KB.

TpApi is a HLLAPI test program with source code available for download at: TpApi.zip - 35 KB.

A Visual Basic interface to NMT/HLLAPI, written by Sheantré Noé, is available for download at: vbapi.zip - 4 KB.

NMTAPI.DLL, included in the 32bits version, is a independent telnet 3270 terminal interface. It can be used as a connection from one application into several host applications. The dll can be used both from a server and a client. A demo application which uses the dll is available at: TpH.zip.