Exchange/SNA Manual

Step 4: Perform the Operation
Using the Exchange/SNA Command Interpreter
2–10 104700 Tandem Computers Incorporated
Receiving a Single File. To receive a single file from the host, use the RECEIVE command
with the END IMMED parameter. This stops the receive operation as soon as the host
sends a type 1 function management header for the given destination subdevice with
end destination selection (EDS) set, which indicates the end of the data stream (file) for
the specified subdevice.
Receiving Multiple Files. There are two ways to receive multiple files from the host by
using a single RECEIVE command; both ways write the files received from the host to
a single file on the Tandem system. If you want to receive multiple files from the host
and you want each file received written to a separate file on the Tandem system, you
must use separate RECEIVE commands, one for each file.
One way to receive multiple files from the host by using a single RECEIVE command
is to use the RECEIVE command with the END DEFER parameter. This parameter
causes the RECEIVE command to receive all data sent from the host to the specified
destination subdevice until you explicitly stop the receive operation by using the
ABORT command (or another command, such as DISCONNECT, that performs an
implicit ABORT operation).
The other way to receive multiple files from the host by using a single RECEIVE
command is to use the RECEIVE command with the END TIMED parameter. This
parameter causes the RECEIVE command to receive all data sent from the host to the
specified destination, as long as the host begins the next data stream within a specified
time period after the last data stream ended. This form of the RECEIVE command
ends automatically when the host system fails to begin a new data stream to the
specified destination subdevice within the specified time period. This time period is
variable; to change the timeout period, use the ENDTIMED parameter in the SET,
RESET, or RJECIS command.
Sending Commands to the Host RJE Subsystem
You can send commands to the host RJE subsystem and receive any output produced
by those commands. To do so, a console subdevice must have been defined when the
line server was started, and a command character must be defined for your command
interpreter.
The Console Subdevice. The CONSOLE configuration parameter is used to define a
console subdevice. Each line server can support only one console subdevice, but the
single console subdevice can be opened by several different processes (such as
Exchange/SNA command interpreters) at once. The maximum number of processes
that can open the console subdevice at once is defined in the CONSOLE parameter.
For more information on the CONSOLE parameter, see the SET command described in
Section 3.
When the host RJE subsystem sends data to the Exchange/SNA console subdevice,
every process that has opened the console subdevice can read the data. In the case of
Exchange/SNA command interpreters, each command interpreter reads all console
data sent by the host and displays the console data on its home terminal.