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Alpha OpenVMS Process Control

This appendix presents some useful tips about managing your Alpha OpenVMS processes. For more information about a specific application development tool, refer either to the product's generic documentation or to the product's chapter in this guide.

Your Compaq documentation contains additional information on these topics.

The following topics are covered in this appendix:

Interrupting and Terminating Oracle Operations

This section explains the following:

Cancelling without Aborting the Oracle Image

To cancel an operation without aborting the Oracle image, press [CONTROL]-C. The current query is cancelled. After pressing [CONTROL]-C, you might need to press the [RETURN] key to bring the prompt back (particularly when you are using command line tools such as SQL*Plus or SVRMGRL).

Cancelling with the Option to Continue

You can also terminate any Oracle operation by pressing [CONTROL]-Y. This returns the DCL prompt ($) with a message that Oracle has been interrupted.

To continue your Oracle session, type "CONTINUE." To terminate the session, type "EXIT".

Typing "EXIT"or any other Alpha OpenVMS command cancels the query and runs down the tool. Typing "EXIT" causes a noticeable delay before the DCL prompt returns or before the requested Alpha OpenVMS command executes because a partial shutdown of your Oracle session occurs.

Known Limitations in Client-Server Connections

Any client tool you are using is connected to Oracle through a client-server SQL*Net connection (for example, by using the VMS Mailbox). If the query is cancelled, the tool shuts down, but no message is sent from the tool to the server to tell it to terminate the server session. On sensing that a client tool has aborted, many SQL*Net protocols send a message to the server that causes the server session to terminate, but some do not. In this case, the server sessions continue indefinitely until Oracle kills the session because the user session has a finite idle-time limit, the system shuts down, or some watchdog process on the node kills the idle process. This is a known limitation.

If a user's terminal unexpectedly disconnects from Alpha OpenVMS while engaged in a client-server connection to Oracle (connecting to Alpha OpenVMS through a LAT terminal or a personal computer is turned off), the client tool is aborted through the [CONTROL]-Y and "EXIT" method. The current query, if any, is cancelled and the tool does a partial shutdown.

Disabling Control Keys

To disable the control keys, enter the command:

$ SET TERM/PASTHRU

Running Oracle Programs as Detached Processes

Sometimes you might want to run programs as detached processes; for example, you might want to run a Pro*C program while you are logged into SQL*Plus or while doing work unrelated to Oracle.

A detached process does not inherit the logical names that its parent has. Consequently, when a program executable is passed to the detached process, the detached process will abort because it cannot find the logical names referenced by the program.

You can work around this problem by invoking the login process LOGINOUT, which maps DCL into the detached process's virtual space. This can execute a command procedure to run the program in the detached process. The command file should:

Set up the proper execution environment by defining the referenced logical names, symbols, and defaults.

Invoke the program to be executed. For example:

$ RUN/DETACH/INPUT=TEST.COM/OUTPUT=TEST.LOG SYS$SYSTEM:LOGINOUT

where TEST.COM is:

$ @DISK$TEST:[ORACLE.DB_TEST]ORAUSER_TEST.COM 
$ RUN <myprog>.EXE

You might need to include certain process quotas to map DCL into the detached process's virtual space. Refer to Compaq's documentation for more information.

C Alpha OpenVMS Process Control