HP OpenVMS DCL Dictionary
Connects your terminal to a specified service available on the local
area network (LAN), establishing one session for communication between
your terminal and that service.
The service node that provides the service must be on the same
extended LAN and must be running at least Version 5.0 of the LAT
SET HOST/LAT service-name
Specifies the name of the service to which you want your terminal
connected. A service is a resource on the LAN. A service often consists
of all of the resources of a computer system. Other examples of
services are a file storage system and an application program running
on a computer system. A computer system that offers one or more
services is called a service node.
If several service nodes offer the same service, and you do not specify
the /NODE=node-name qualifier, your terminal connects to the service
node that is the least busy.
To display a list of services on your LAN, use the LAT Control Program
(LATCP) SHOW SERVICES command. See the HP OpenVMS System Management Utilities Reference Manual.
The SET HOST/LAT command allows you to connect your terminal to a
specified service, establishing one LAT session for communication
between your terminal and that service. (For an overview of the LAT
protocol and its advantages, see the HP OpenVMS System Manager's Manual.)
The service node that provides the service must be on the same extended
LAN and must be running at least Version 5.0 of the LAT protocol.
Some services are password protected. You are prompted for a password
unless you specify the password with the /PASSWORD qualifier.
Once the connection to the service is made, you can interact with the
service as if your terminal is directly connected to it. Some services
will prompt you. For example, if the service is an OpenVMS system, it
prompts you for a user name and password. You must have an account on
the service node to log in.
Press the disconnect character to end the LAT session and return to DCL
command level on your local system. With some services, such as general
timesharing services like OpenVMS, you can end the LAT session by
logging out of the service. The default disconnect character is Ctrl/\.
Use the /DISCONNECT qualifier to change the default disconnect
Specifies whether connection attempts should be retried automatically
when a connection fails because a service is unknown or unavailable, or
because a node is unknown or unreachable. Also specifies that
reconnects should be attempted automatically if a service has
disconnected abnormally. The default is /NOAUTOCONNECT.
Causes an OpenVMS Username: prompt to appear with no user action when a
SET HOST/LAT command is issued.
On a terminal server port, you can configure the port to have
AUTOPROMPT disabled (/NOAUTOPROMPT) so that you are required to press
Return when connecting to a node to get the Username: prompt; however,
when connecting to a reverse LAT service, the AUTOPROMPT characteristic
should be disabled.
Defines a character that generates a break on lines that expect a break
rather than a carriage return. To generate a break, press the Ctrl and
break-character keys together. The default
break-character value is the tilde (~).
You can select any ASCII character between @ and Z, except C, M, Q, S,
Y, and the left bracket ([). You cannot select a character that is
already defined as the disconnect character.
Specifies the port on a node to which you want to connect. The /NODE
qualifier is required when you specify the /DESTINATION_PORT qualifier.
The port must be available and must offer the service you specify.
OpenVMS and certain other LAT service node systems ignore the
Allows a modem attached to the outgoing terminal line to be autodialed
using the autodial protocol of that modem. The NUMBER keyword is the
telephone number to be autodialed and is a required parameter.
The MODEM_TYPE keyword is optional. It can be used to specify any of
the following modem types:
- DMCL (any modem that uses the DEC Modem Command Language)
- DF03 (default)
Each modem type requires a specific modem dialer code. Check with your
system manager to see which modem dialer codes are installed on your
In addition, the MODEM_TYPE keyword can be used to specify a modem type
other than DF03, DF112, or DMCL. A template is provided for users
interested in supporting other modems with autodial capabilities (see
Defines the character that you can use to disconnect from a remote
session. To generate a disconnect, press the Ctrl and
disconnect-character keys together. The default
disconnect-character is the backslash (\).
You can select any ASCII character from @ through Z, except C, M, Q, S,
Y, and the left bracket ([). For example, if you specify /DISCONNECT=A,
Ctrl/A will be the disconnect character. You cannot select a character
that is already defined as the break character.
Determines whether the outgoing terminal line supports 8-bit or 7-bit
characters. By default, 8-bit characters are supported. If you specify
/NOEIGHT_BIT, then 7-bit characters are supported.
To change the number of bits per character on the remote terminal
server port, that port must have the REMOTE MODIFICATION characteristic
The /FRAME=n qualifier allows a user making a LAT connection
to a remote system to specify the number of data bits that the terminal
driver expects for every character that is input or output. The value
of n can be from 5 to 8. The default value depends on the
settings for the terminal established by the /PARITY and /EIGHT_BIT
qualifiers. The following example specifies a character frame size of 7
bits per character:
$ SET HOST/LAT /FRAME=7 DIAL_OUT_SVC
Logs all data that is delivered during the LAT session. If you do not
specify a log file, the data is stored in the file SETHOST_LAT.LOG.
Specifies the node that offers the service to which you want to
connect. Failover is not performed if the connection fails.
Specifies the password required by a service that is password
protected. If you do not specify the /PASSWORD qualifier when
requesting a connection to a password-protected service, you are
prompted for a password.
When connecting to a reverse LAT service that is already in use (such
as a dial out modem), you are notified that the service is in use and
the SET HOST/LAT command terminates. However, LAT can allow incoming
connections to be queued to any reverse LAT service that supports
service queueing, which enables users to be placed on a queue when
using reverse LAT services.
LAT reports your position in the queue. When the resource becomes
available, you are immediately notified. You can cancel the queued
connection by pressing Ctrl/Y and terminating the SET HOST /LAT command.
Sets the baud rate at which the terminal receives and transmits data.
If the input and output rates are the same, specify the qualifier as
Not all terminals support different input and output baud rates. For
specific information on baud rates for your terminal, consult the
manual for that terminal.
The default transmission rates are installation dependent.
The valid values for input and output baud rates are as follows:
300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600
If you select an invalid or unsupported speed, the terminal line speed
will remain set at its previous value.
To change the speed on the terminal server port, the REMOTE
MODIFICATION characteristic must be enabled on that terminal server
When initiating a connection, SET HOST/LAT may attempt to set terminal
server port characteristics, such as the speed and the default speed
for a LAT device. If the device connected to the terminal server port
has a fixed speed (such as a dial-out modem) and you do not want the
host to try to change this, disable the REMOTE MODIFICATION
characteristic on that port using the following command:
Local> DEFINE PORT x REMOTE MODIFICATION DISABLE
Local> LOGOUT PORT x
Use the following command for terminal servers that support the CHANGE
Local> CHANGE PORT x REMOTE MODIFICATION DISABLE
$ SET HOST/LAT SORTER
%LAT-S-CONNECTED, session to SORTER established
%LAT-I-TODISCON, type ^\ to disconnect the session
BARKER logged out at 30-DEC-2001 11:04:51.45
%LAT-I-DISCONNECTED, session disconnected from SORTER
-LAT-I-END, control returned to node HOME
This SET HOST/LAT command connects the user to the service SORTER,
which is a computer system. The first message confirms that the user
has been connected to that service. The second message informs the user
how to disconnect the session. (The user can also disconnect the
session by logging out from SORTER.) SORTER then prompts for the
username and password. Use the normal login procedure to log in to the
system. When the user logs out of the service SORTER, the terminal
displays the DCL command prompt of the user's local processor system
$ SET HOST/LAT/DESTINATION_PORT=BOSTON-
_$ /NODE=STATE/DISCONNECT=F BUDGET
This command connects the user's terminal to the service BUDGET that is
offered on port BOSTON, on service node STATE. The user can disconnect
the session by pressing Ctrl/F.
$ SET HOST/LAT PURSE
This command attempts to connect the user's terminal to the service
PURSE. The service PURSE is password protected, so the user is prompted
for a password. The user could have specified the password within the
SET HOST/LAT command, as shown in the next example.
$ SET HOST/LAT/PASSWORD=BEOR PURSE
This command connects the user's terminal to the password-protected
service PURSE. The password is BEOR.