su and/or ksh change history file's group and ownership

[Amir Sadr]

I've just noticed that during Ksh, becoming super user via /bin/su will
change the owner and group ID of $HISTFILE (in my case $HOME/.kshistory)
to root.  Once I become a regular user again, the group and owner ID of the
history file however remain as root.  This will, I assume, force Ksh to keep
a history of my session in core (since I can still walk through my commands).
But once I terminate Ksh and restart another one, not only the commands
issued after su are lost, but the new Ksh no longer has permission to
write to $HISTFILE.  And thus even though no error or warning message is
given, any recorded history is lost once a Ksh session is terminated.  

History files should be read and write protected from others and in fact 
that is the way Ksh creates them if they do not exist.  I suppose this
problem could be ridden if I allow others write permission to my history
file, but I don't think this is reasonable.  Or I could just avoid
become super user by using /bin/su and instead login as root.

Has anyone else noticed this phenomenon, or is it just me doing something
wrong?  I am running version 3.51m and I'd be interested to hear if others
have experienced the same?  I can't recall, but I think a new Ksh was 
delivered as part of 3.51m upgrade.  Did the 3.51a version do this too?
I hadn't noticed this then?  Can this some how be patched?  Thank you-
-- 
- Amir Sadr,  Dept. of Computer Science          amir at ms.uky.edu
- University of Kentucky                         amir at UKMA.BITNET
- Lexington,  KY 40506-0027                      [rutgers,uunet]!ukma!amir
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