DAQ DataViewer Lockup Solution.
(From elog entry by Dave Barker, 8/24/2000 10:37:15)

For the cases where the dataviewer will not run, no matter how many times
you try it, and the last message on the status screen is;

              Done connecting to the data server

there are no more messages, and all dataviewer windows are dead.

The problem is caused by user owned message queues which have been left
hanging, the user must kill all outstanding message queues before dataviewer
can be restarted.

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Recovery Procedure:

1) Ensure all dataviewers and their associated tasks have been terminated.
2) Get a list of your message queues, use the command;
       > ipcs -b
   An example output is (running as user barker);
        IPC status from  as of Thu Aug 24 10:25:11 PDT 2000
        T         ID      KEY        MODE        OWNER    GROUP QBYTES
        Message Queues:
        q        150   0x542      -Rrw-rw-rw-   barker cdsadmin   4096
        q        151   0x5e1      -Rrw-rw-rw-   barker cdsadmin   4096
        T         ID      KEY        MODE        OWNER    GROUP      SEGSZ
        Shared Memory:
        m          0   0x5000098c --rw-r--r--     root     root          4
        T         ID      KEY        MODE        OWNER    GROUP NSEMS
        Semaphores:
   So, user barker has two queues, with ids 150 and 151.
3) Delete your message queues (the ones belonging to you).
   In this example, this would be done with;
        > ipcrm -q 150
        > ipcrm -q 151
4) Try to restart the dataviewer, all should be well.