From: ahoward <ahoward@...>
Date: 2003-02-07T02:11:11+09:00
Subject: pipe.close -> Broken pipe/DRb madness


system ruby'ists-

on solairs 5.9 and ruby 1.6.8 this is a very silly thing to do :

  pipe = IO.popen 'while (test 1); do date; done'

since you can neither close the pipe nor exit your program willout send a
billion 'Broken pipe' messages to the screen.  now, i realize this is a very
silly thing to do, and the pipe.close waits should call pclose, which would
wait4 for the child to die.  my question is, shouldn't their be a way to
signal a pipe's child that it should die?  shouldn't IO.close do this?  am i
just expecting too much?

what i am attempting to do is fork off several processes which will then fire
up some DRb servers.  the problem is that i want the parent to be able to
learn the uri of each of the 'child' DRb objects without using sysvipc.  i
attempted to do this using a PStore but it seems to be poorly behaved where
fork/threads are concerned.  so, i was thinking that if i could fork in such a
manner that i would maintain communications between parent and child
(pipe/fork or popen) that could solve my problems.  the problems with this is
that DRb servers (forked children) _never die_ as in the 'while' loop above,
and thus program shut down becomes difficult.  i don't know if any of that
made sense, but ideas/suggestions are welcome.

-a

-- 

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 | Ara Howard
 | NOAA Forecast Systems Laboratory
 | Information and Technology Services
 | Data Systems Group
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 | Email: ahoward@fsl.noaa.gov
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 | Fax:    303-497-7259
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