|
|
Privileged Mode
Adds/deletes/lists terminals used for demonstrating System Debug.
DEMO
DEMO LIST
DEMO ADD ldevs
DEMO DELETE ldevs
The DEMO command is used for giving demonstrations of System
Debug. With this command, the user is able to enslave up to 50 terminals.
Each of the enslaved terminals receives all input and output generated
by System Debug. Output generated by the CI through the use of the ":"
command or CIGETVAR and CIPUTVAR functions is not sent to the
enslaved terminals.
Please read and heed the warnings listed in "Limitations, Restrictions."
- DEMO
List the terminal LDEV's that currently are receiving System Debug
I/O.
- DEMO LIST
Both command forms are identically supported.
- DEMO ADD
This keyword tells System Debug to add the following LDEVs to the list
of terminals to receive a copy of all System Debug I/O.
- DEMO DELETE
This keyword tells System Debug to remove the following LDEVs from the
list of terminals that receive a copy of all System Debug I/O.
- ldevs
A list of terminal LDEV numbers (logical device numbers), separated by
blanks or commas. A note of caution: remember that the LDEV numbers are
interpreted using the current input base for System Debug.
$nmdat > demo
No demonstration terminals are defined
$nmdat > demo add #200 #201 #205 #206
$nmdat > demo list
DEMO LDEVS (#): 200 201 205 206
First, check to see if any demonstration LDEVs have been specified.
Next, add four LDEVs to the list of terminals to receive a copy
of DAT's input and output stream. As soon as the DEMO ADD
command is processed, the indicated terminals
begin receiving I/O. Finally, display the list of demonstration terminals.
A total of 50 demonstration LDEVs are supported.
The functionality is implemented with low-level I/O routines.
I/O is done directly to the LDEV. No attempt is made to lock or
obtain ownership of the LDEV before sending data to it. Nonpreemptive
I/O is used when sending data to the LDEVs. Therefore, if a read
is pending at the LDEV (For example, the CI prompt), System Debug
blocks until the pending read is satisfied. It is good practice
to free up the LDEVs that will be used during a demonstration by issuing the
:RESTORE command at each terminal (do not REPLY to the resulting
tape request). This removes any pending I/O from the LDEV. When
the demonstration is finished, break out of the RESTORE process
and issue an ABORT command.
No validation of LDEV numbers is performed. If you give an
ldev, then no matter what the value is, System Debug tries
to write to it!
The same LDEV may be specified more than once, in which case the LDEV is sent
a copy of any I/O for each occurrence in the list of LDEVs.
The Control-S/Control-Q/stop keys suspend output only for
the master terminal (that is, the one where the demonstration is
being run). All of the enslaved terminals continue to receive output
as an uninterrupted flow.
|