The CONNECT command connects you to a separate process, as opposed to
the SPAWN and ATTACH commands, which create and attach subprocesses.
The CONNECT command is useful when you are logged in to the system
using telecommunications lines. If there is noise over the line and you
lose the carrier signal, your process does not terminate. After you log
in again, you can reconnect to the original process and log out of your
To use the CONNECT command, the virtual terminal feature must be
enabled for your system with the System Manager utility (SYSMAN) on
OpenVMS Alpha systems and the System Generation utility (SYSGEN) on
OpenVMS VAX systems.
If virtual terminals are allowed on your system, use the SET
TERMINAL/DISCONNECT/PERMANENT command to enable the virtual terminal
characteristic for a particular physical terminal. When you enable this
characteristic, a virtual terminal is created when a user logs in to
the physical terminal. The physical terminal is connected to the
virtual terminal, which is in turn connected to the process.
For new virtual terminals, you must first set the TT2$V_DISCONNECT bit
in the TTY_DEFCHAR2 system parameter and reboot the system. This is
done by creating the virtual device VTA0: using the ttdriver. For
example, on Alpha:
$ RUN SYS$SYSTEM:SYSMAN
SYSMAN> IO CONNECT/NOADAPTER/DRIVER=SYS$LOADABLE_IMAGES:SYS$TTDRIVER VTA0:
$ RUN SYS$SYSTEM:SYSGEN
SYSGEN> CONNECT /NOADAPTER/DRIVER=TTDRIVER VTA0:
When the connection between the physical terminal and the virtual
terminal is broken, you are logged out of your current process (and any
images that the process is executing stop running) unless you have
specified the /NOLOGOUT qualifier.
If you have specified the /NOLOGOUT qualifier, the process remains
connected to the virtual terminal. If the process is executing an
image, it continues until the process needs terminal input or attempts
to write to the terminal. At that point, the process waits until the
physical terminal is reconnected to the virtual terminal.
You can connect to a virtual terminal even if you are not currently
using a virtual terminal; however, to log out of your current process
you must use the CONNECT command with the /LOGOUT qualifier. If you
connect to a virtual terminal from another virtual terminal, you can
save your current process by using the /NOLOGOUT qualifier.
Controls whether the CONTINUE command is executed in the current
process just before connecting to another process. This qualifier
allows an interrupted image to continue processing after you connect to
The /CONTINUE qualifier is incompatible with the /LOGOUT qualifier.
Logs out your current process when you connect to another process using
a virtual terminal.
When you enter the CONNECT command from a process that is not connected
to a virtual terminal, you must specify the /LOGOUT qualifier;
otherwise, DCL displays an error message.
The /LOGOUT qualifier is incompatible with the /CONTINUE qualifier.
In this example, you use the RUN command to execute the image
AVERAGE.EXE. You enter this command from a terminal that is connected
to a virtual terminal. Next, you press Ctrl/Y to interrupt the image.
After you interrupt the image, enter the CONNECT command with the
/CONTINUE qualifier. This operation issues the CONTINUE command, so the
image continues to run and connects you to another virtual terminal.
You can reconnect to the process later.
This example shows how to reconnect to your original process after you
have lost the carrier signal. First, you must log in again and create a
new process. After you log in, enter the SHOW USERS/FULL command to
determine the virtual terminal name for your initial process. Then
enter the CONNECT command to connect to the virtual terminal associated
with your original process. The process from which you enter the
CONNECT command is logged out because you have not specified any
When you reconnect to the original process, you continue running the
image that you were running when you lost the carrier signal. In this
example, the user SMITH was at interactive level when the connection