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OpenVMS mailbox - logging

Posted: Wed Sep 15, 2021 1:25 pm
by garyrevell
Hi all,

We've got a complex application that makes a lot of use of mailbox interprocess communication, there are many processes and differing messages.

My question are.... is there a way of seeing what messages & contents are in the mbx without actually reading them via a $QIO(W)? Perhaps there's a tool or example program that allows access to the data in an mbx via system services etc?

Thanks!

Gary

Re: OpenVMS mailbox - logging

Posted: Tue Sep 21, 2021 9:23 am
by volkerhalle
Gary,

just checked - I did not receive any private message in the VSI forum.

You can use my mail address from my MBOX source change comment from 2005, it's still valid ;-)

Volker.

Re: OpenVMS mailbox - logging

Posted: Tue Sep 21, 2021 10:15 am
by imiller
MBU is a program for looking at, creating and deleting mailboxes.
MBMON is for seeing what is being written to mailbox as it happens and is intended to aid debugging of applications which use mailboxes for interprocess communcations.

I wrote them many years ago and not looked at them for years. I've not built them on recent versions of VMS but could have a go if you tell me which version of VMS you are using.

Re: OpenVMS mailbox - logging

Posted: Tue Sep 21, 2021 1:06 pm
by arne_v
VMS mailboxes are brilliant in the context where memory is counted in KB.

But if memory is counted in GB then it may not the optimal solution.

Switching to a standard message queue (VSI supports ActiveMQ) would make stuff like this easy.

writer-->MBX-->reader becomes writer-->MQ-->reader and are basically the same, but there are a lot extras.

Getting messages written and read logged is just something that is configured in the log configuration.