(9931) File Access (or Creation) Notifications?

Archive of the OpenVMS Ask the Wizard (ATW) questions and answers database.
Locked

Topic author
User
Visitor
Posts: 0
Joined: Mon Jan 10, 2022 8:16 am
Reputation: 0
Status: Offline

(9931) File Access (or Creation) Notifications?

Post by User » Sun Nov 28, 2004 8:26 am

We have a shared directory where a few hundred people have access. The files are owned by a RUN account so that the one account can control the files and is responsible for the cleanup.

We have someone creating a new version of file every ten minutes and it is not open for long. I know that opcom can be setup on a file but I cant find the instructions to make a file send an alert when it is accessed.

How do I add the specific file or modify the file so that it sends an alert when a new version is created?
Last edited by marty.stu on Mon Jan 10, 2022 9:19 am, edited 1 time in total.


Wizard
Visitor
Posts: 0
Joined: Mon Jan 10, 2022 8:17 am
Reputation: 0
Status: Offline

Re: (9931) File Access (or Creation) Notifications?

Post by Wizard » Mon Nov 29, 2004 8:26 am

If there is an existing and lower version of the file, add an audit or alarm ACE to the existing file:

Code: Select all

$ SET SECURITY/ACL=(ALARM=SECURITY,ACCESS=WRITE+DELETE+SUCCESS) -
filename
Alarms target the operator consoles enabled for SECURITY (see the command $ REPLY/ENABLE=SECURITY) while audits target the security journal (use $ ANALYZE/AUDIT) to find them.

If there is not 't an existing file, you can place a similar audit or alarm ACE on the directory. This may generate significant traffic, but if the interval really is only 10 minutes, that shouldn't be an issue.

Experiment with an ALARM ACE to make sure it does what you want.

The interesting part here is that you can create an application that receives and can processes these messages directly, using the available security listener mechanisms; see the DCL commands $ SET AUDIT/NOLISTENER and $ SET AUDIT/LISTENER as a start.

Topics such as (4818) and (5819), and possibly (6610), will be of some interest here, too, as will a modification of the tool itself; changes to the tool to send along the desired and appropriate notifications. Like creation, access can also be audited.

Of course, it is also possible to use a lock within the various application images and processes, and to particularly use this lock as a doorbell; to trigger a cluster-wide operation that either closes and re-opens the file as required, or that controls application and process activity when the file contents are otherwise updated.

The OpenVMS Wizard would tend to use one of the available access coordination (communications) mechanisms within the applications; cooperating interprocess communications mechanisms and designs.
Last edited by marty.stu on Mon Jan 10, 2022 9:19 am, edited 2 times in total.

Locked