elementary problems

[Mark Callow]

In article <6094 at alvin.mcnc.org>, spl at mcnc.org (Steve Lamont) writes:
> Our machine goes graphically catatonic when the nameserver dies on us.  If a
> person is already logged on and has several windows open, everything still
> works in the already opened windows, but no new windows may be created.  It
> seems that every time a new wsh is spawned, the wsh has to look up who it is
> running on so that it can talk to the window manager. 

Both wsh and the NeWS server use the host database access routines documented
in section 3 of the manual.  These routines go to the nameserver if you
have a /usr/etc/resolv.conf file.  There is nothing that wsh or NeWS can
do to prevent this.

wsh looks up localhost and probably doesn't have a problem as long as you
have software loopback correctly configured.  But when NeWS receives the
connection request is does a getpeername(3) followed by a gethostbyaddress(3)
to determine the name of the host attempting to make the connection.
This is almost certainly the lookup that fails.

> 
> If you are not logged on and attempt to do so, the screen will blank, a white
> cursor arrow will appear for a moment or two, and then the screen returns to
> the login prompt with a message to the effect that the window manager has
> exited with an error (or status, I don't recall the precise wording) code of
> 1.  Effectively, the machine become useless, graphically, until the
nameserver
> returns from the dead.

The NeWS server looks up its own hostname using gethostbyname to find its
official name.  This status message means that the lookup failed.  (There
is an fprintf right before the exit that explains the problem.  For reasons
I don't yet understand the message fails to appear.)

> 
> Is there any easy (or not so easy) way to make the machine default back to
> host tables or in some other manner figure out who it is so that it
can open a
> graphic window?

I don't know of any in release 3.2.  In the next release there is a new
call sethostresorder which essentially lets you define a search path for
resolving host database queries.  You can be sure I will modify the NeWS
server to use this call.  It will then try the /etc/hosts file when the
nameserver fails.

> 
> BTW, we have a 4D/280GTX running 3.2.  We have the idiot pandora stuff turned
> off at login and don't use WorkSpace if we can avoid it (I could rant at
> length about turning a powerful computer into a Macintosh, but I'll leave it
> at for an experienced UNIX user; e.g., one with more than five minutes
> experience, silly graphical interfaces are more of a hinderance than a help).

Personally I love pandora but then I hate typing.  I also like using
WorkSpace but we all know it leaves something to be desired when doing software
development.  The first release was only ever intended to support users
running applications.  Future releases will have features to support software
developers.  I also find the visual adminstration tools very helpful especially
the printer tool.  Before that I was always seeking out our printer expert
to ask him how to do what I needed.  Now I can do it myself.  I was
a system adminstrator for several years but that system V lp stuff is
simply awful and my brain refused to learn it.  I'm so glad we've hidden it.

Do you hate all graphical tools?  We have some really neat ones coming.
Don't miss out.
--
>From the TARDIS of Mark Callow
msc at ramoth.sgi.com, ...{ames,decwrl}!sgi!msc
"There is much virtue in a window.  It is to a human being as a frame is to
a painting, as a proscenium to a play.  It strongly defines its content."