I have few ugly shell scripts which do a lot of WHOIS queries, which I've found are prone to hang for a long time. The simple thing to do is to hunt for whois queries, then, and periodically kill them:
while sleep 600
do
ps aux | awk '/[w]hois/ {print $2}' | xargs kill
done
Of course, this is a bit indiscriminate: it kills any WHOIS process
that happens to be running at the moment.
Best would be to avoid the hung processes at all. But I haven't figured
that one out yet.
Better, though, is to throw a delay into the processing -- find out
which processes are there, then attempt to kill them later. *Most*
WHOIS queries return quickly. Actually, most of 'em return *really*
quickly since I use a caching whois clinet (jwhois, since you're
asking). But let's say I need a 30 second delay. Best not to dally
*too* long or I might roll through my PID table.
The inspiration was an old recipie from the O'Reilly _UNIX Power Tools_
book for moving a filesystem with tar (this back before rsync or cp -pdR,
etc., could do this reliably). Basically, you tar to stdout, then
extract from stdin, from a shell which has been relocated:
tar cf - . | ( cd /otherdir; tar xvf - )
I found that it didn't work trying to pipe through sleep (I guess the
lesson is: don't smoke in bed):
echo foo | sleep 30 | sed -e 's/foo/bar/'
...but piping through a subshell (that's what the () gives you) *does*
work:
echo foo | ( sleep 3; cat ) | sed -e 's/foo/bar/'
So now I've got:
while sleep 600
do
ps aux | awk '/[w]hois/ {print $2}' | ( sleep 30; cat ) | xargs kill
done
And reading this post as I write it, I realize I've also won myself a
gratuitous use of cat award, so we can further simplify to:
while sleep 600
do
ps aux | awk '/[w]hois/ {print $2}' | ( sleep 30; xargs kill )
done
Enjoy.
Peace.
--
Karsten M. Self <[EMAIL PROTECTED]> http://kmself.home.netcom.com/
What Part of "Gestalt" don't you understand?
I mean once word leaks out that a pirate has gone soft, people begin
to disobey you and it's nothing but work, work, work all the time.
- Princess Bride
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