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Edited by John Burke

An interesting thing occurred to us this month, when we tried to convert a very large MPE file to bytestream.
record count: 102370
record length: 25158
bytes: 2575424460, or approx. 2.5 GB
Unbeknownst to us, the tobyte program has a 2Gb limit, or so it seems. Using the POSIX command ‘tobyte <source> <dest>’ always produced a file with a bytecount of 2147483647 (which is one byte less than 2Gb). Why is this the case, and is there a workaround?

Michael Berkowitz replies:
The problem is not with tobyte. The answer is the way bytestream files are implemented on the HP 3000. The file system is record oriented for all file types including bytestream files. Bytestream files are simulated by making 1 byte records. However the maximum number of records that any file can have, a 32 bit integer, has never changed.
So the maximum number of bytes a 1 byte/record file can have is 2147483647. This number cannot be made larger, say to 64 bits unless all file intrinsics that reference a record pointer are changed to allow the larger value. Now the fact that tobyte didn’t give an error when converting too large of a file should be considered a bug.

Mark Wonsil adds:
All is not lost though. Instead of writing the whole input file to one output file, consider piping the result of tobyte to split. Check out the man page.

How do I set my prompt setting in the startup script?

John Burke replies:
Here’s what I do for my prompt:
This yields, for example,

The SYSINFO program just crashed our N-Class system running MPE/iX 7.0. HP told us don’t run the program. Is the problem is related to my N-Class or to MPE/iX 7.0?

John Burke replies:
SYSINFO is one of those darling little programs that is available from HP on every system but technically unsupported. The Catch-22 comes in when in various documentation HP suggests you run SYSINFO to check something or other, but then will not support you if something goes wrong.
SYSINFO in the past was notorious for crashing loaded, multi-processor systems when “all”, “mem”, “module” or “cpu” commands were called. As far as I know, this is still a potential problem. It also had the nasty habit of breaking mirrors in a Mirror/iX environment though I believe that has been fixed.

As of 6.5 with STM (may that program die a horrible death) there are additional complications; for example, “mem” can just start looping chewing up CPU time and never returning information if STM is not running correctly. There are other reports about bogus information being returned. SYSINFO can be a very useful program for displaying information about your system. However, it must be run with great care. But the question was about ABORTJOB not working.

I want to add a DDS-2 drive to our 918/LX which already has two disks and one DDS-1 C1504 tape drive connected. How can I find out which SCSI addresses are already used by the DDS-1 and the discs without removing the drives to inspect jumpers?

Wirt Atmar replies:
Use the IO command in SYSINFO.PRVXL.TELESUP.

I am trying to test my disaster recovery scenario by installing a CSLT tape onto to a 9x8 that was produced on a 9x7 . How can I avoid hardware config errors?

Robert Schlosser replies:
After the install you will need to specify a config group when you do the start norecovery. For a 9x8 system you may want to try: START NORECOVERY GROUP=CONFG9X8. This will give you the basic hardware configuration to start with so you can add whatever else is attached. I would also suggest running mapper from the ISL prompt to get the correct paths to all devices attached.

I would like to set up an HP 3000 as a file server. In one of my accounts I want to have a share for my 100 users pointing to a separate directory in this account. The homes section in smb.conf normally points to the home group of the user, which is the same for all of them and is not helpful. Is there another way of solving the problem, or must I configure more the 100 shares?

Mark Wonsil replies:
I saw a clever little trick in Unix that should work on MPE:

path = /ACCT/SHARES/%U

This creates a share name that is the same as the username and then it points the files to a directory under the SHARES group.

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