HCON Processes

HCON emulator and file transfer sessions are established, maintained, and stopped by these processes:

The hcondmn subsystem provides a focal point to coordinate the various HCON sessions and negotiate conflicts throughout the system. The subsystem assigns a unique identifier to each session, providing the e789, xhcon, e789cln, and fxfer commands, and the HCON HLLAPI programs with a label to identify that session on the local system.

When the e789 or xhcon command is invoked, an e789 or xhconx process is started. The e789 process starts the e789x process for each session. For example:

e789 bdh

starts one instance of the e789 process and three instances of the e789x process, for sessions b , d , and h. The xhcon process starts the xhconx process for each session. For example, enter the following to start one instance of the xhcon process and three instances of xhconx process for sessions b, d, and h:

xhcon bdh

Each instance of the e789 process manages the e789x processes associated with it. Each invocation of the e789 process runs independently of the other e789 processes invoked on the same system. For SNA DFT sessions, the e789x process invokes an SNA protocol process (e789lus) to manage the SNA protocol.

The file transfer starts a separate child process. The dfxfer process is invoked when a file transfer begins with:

• fxfer command
• fxfer function
• g32_fxfer function
• File transfer requests through the hconutil command

The HCON Processes figure shows the parent and child process relationship.

hcondmn Subsystem

The hcondmn subsystem is a daemon invoked at startup on any system with the HCON program installed. During installation, instructions are placed in the inittab file. These instructions direct the System Resource Controller (SRC) to start the hcondmn subsystem each time the system is turned on. The subsystem can also be started using the smit hcon Control option. Use the ps command to determine if the hcondmn subsystem is running.

The subsystem remains in a wait state until requests from HCON internal components arrive. Any process establishing an HCON session communicates with the hcondmn subsystem to register that session.

The hcondmn subsystem:

• Resolves session name conflicts at session startup.
• Maintains and manages internal software structures such as queues, shared segments, and logical terminal names for each session on the system.
• Initializes interfaces to each session (requested by HCON applications) to establish internal communication.
• Removes the resources associated with each session when the session ends.

The hcondmn subsystem starts and stops using the following commands:

/usr/lib/hcon/sthcondmn

/usr/bin/stopsrc -f -s hcon

Attention: Do not stop the hcondmn subsystem unless under directions from customer support, or if installing or updating HCON software. Any process establishing an HCON session communicates with the hcondmn subsystem to register that session. Be sure all HCON activity has ceased before stopping the hcondmn subsystem.

e789 Process

The e789 process starts each time a display session is started using the e789 command. The e789 process contacts the hcondmn subsystem to establish the requested display session or sessions. The hcondmn subsystem allocates the appropriate storage space for each session and passes a return code to the e789 process. The e789 process creates an e789x child process for each display session.

xhcon Process

The xhcon process starts each time a display session is started using the xhcon command. The xhcon process contacts the hcondmn subsystem to establish the requested display session or sessions. The hcondmn subsystem allocates the appropriate storage space for each session and passes a return code to the xhcon process. The xhcon process creates an xhconx child process for each display session.

e789pr Process

The e789pr process starts each time a printer session is started using the e789pr command. The e789pr process contacts the hcondmn subsystem to establish the requested printer session or sessions. The hcondmn subsystem allocates the appropriate storage space for each printer session and passes a return code to the e789pr process. The e789pr process creates an e789x child process for each printer session.

e789x Process

The e789x child process starts for each session on the system. The e789x child process can be started by:

• e789 process
• File transfer executed with an implicit logon
• HLLAPI program executed with implicit logon

The e789x process attaches to the storage space established for that session by the hcondmn subsystem. For a DFT display session that is SNA-attached, the e789x process invokes an e789lus process to manage the SNA protocol.

xhconx Process

The xhconx child process starts for each session on the system. The xhconx child process can be started by using the xhcon process.

The xhconx process attaches to the storage space established for that session by the hcondmn subsystem. For a DFT display session that is SNA-attached, the xhconx process invokes an e789lus process to manage the SNA protocol.

e789lus Process

The e789lus child process is invoked by the e789x process for each SNA DFT display session. The e789lus process manages the SNA protocol, while the e789x process manages the 3270 data stream.