Exchange/RJE Manual

Step-by-Step Instructions
Using the Exchange/RJE Programmatic Interface
4–8 104698 Tandem Computers Incorporated
Block Mode With 2780/3780 Blocking
Block mode with 2780 blocking and block mode with 3780 blocking provide all
features of the standard 2780-emulation and 3780-emulation modes, respectively. In
addition, block mode with 2780 blocking and block mode with 3780 blocking allow
you to select the size of the text portion of a transmission block (BLOCKSIZE) up to
4084 bytes and allow larger record sizes (up to BLOCKSIZE for block mode with 2780
blocking and up to BLOCKSIZE -1 for block mode with 3780 blocking).
You select 2780 or 3780 blocking when you issue a CONNECT command; you can
switch between 2780 and 3780 blocking by disconnecting and reconnecting.
Block Mode Without Blocking
Block-mode without blocking operations transmit and receive each record as a single
block, up to 4084 bytes. You can use block mode to transfer large records.
The Trace Server You can use the Exchange/RJE trace server to log the communication between the line
server and the underlying communications process.
To use the trace server with your programs, follow the steps below:
1. Start the command interpreter.
2. Start a named line server or connect to an existing line server using the CONNECT
command.
3. Start the trace server using the TRACE command.
4. Disconnect and exit from the command interpreter.
The trace server is now running and logging the communications handled by the line
server you connected to in Step 2 above. To log your program’s communications with
the remote system, have your program use this line server.
To stop the trace server, start the command interpreter, connect to the same line server
again, and use the TRACE command to stop the trace server. Use the DUMP
command to format and list the trace of your program’s communications.
Step-by-Step
Instructions
Most uses of the Exchange/RJE programmatic interface follow the same general
sequence of steps. This sequence is outlined below. (Steps 2, 3, and 4 are only
required if your program calls the NEWPROCESS procedure to start the line server.)
1. Start the line server.
2. Open the line server.
3. Send a startup message to the line server.
4. Close the line server.
5. Open the line server.
6. Establish a connection with the data communications line.
7. Set the operational parameters.