20010308: McIDAS: Locked file (LOCAL.NAM)

>From: Erick Lorenz <address@hidden>
>Organization: UC Davis
>Keywords: 200103090125.f291PqL26988 McIDAS-X LWPATH.NAM

Erick,

>I tried to edit my ~mcidas/data/LOCAL.NAM file using emacs.
>
>As soon as I tried to change some thing I got the following message:
>
>.../mcidas/data/LOCAL.NAM locked by mcidas@localh... (pid 12208): (s, q, p,
>?)? 

This seems to say that there may be a another edit session of some kind that
has/had this file opened.

>I assume that mcidas@localh... is mcidas@localhost.

I would guess that is correct.

>There is currently no pid 12208 running.

If this is a Linux box, then I would check for the existence of a file
in the .../mcidas/data directory named .LOCAL.NAM.swp.  'vi' will
create such a file.  Notice the leading '.'.  The swap file used by the
editor will be a hidden file!

>Could this be caused by a mcidas session that was aborted rather than
>shutdown?

No.  McIDAS sessions do not use this file at all.  The LOCAL.NAM file
concept was one I introduced to get folks to take example REDIRECTion
entries in EXAMPLE.NAM and edit them to change directory locations to
match their setup.

>Could it be caused by a mcidas session running on another host which uses this
>machine's software and files?

No, not by a McIDAS session.  Again, McIDAS does not explicitly know about
LOCAL.NAM.

>Is there a simple way to unlock the file?

I am betting that this _is_ on a Linux box, and that there is a .swp
file that is/was used by an vi session on this or some other machine.
Emacs is probably trying to protect you from editing a file that is
open for edit by another editor.  Finding and removing the
.LOCAL.NAM.swp file should then allow you to successfully edit LOCAL.NAM.

If there is no .swp file, then the problem may be NFS related.  In this
case, the only thing that would make sense is that the file actually
resides on a different machine, and somehow it looks locked to your
machine.  If this is the problem (and I actually have seen this on
another users network), it may be an indication of a need for a reboot,
or that your system has been hacked (this was the problme on the other
users machine).  Before worrying too much about a hack, try rebooting
to see if the lock goes away.

>Thank you

Please let me know if either the .swp file or an NFS stale file handle
was the problem.

Tom