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Date: Wed, 16 Jul 2014 10:31:22 +0100
From: Karl Pielorz <kpielorz_lst@tdx.co.uk>
To: freebsd-questions@freebsd.org
Subject: sh 'sleep' and trap?
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Hi All,

I have a script, similar to this:

"
#!/bin/sh

echo $$ >/var/run/mypid.pid
trap "rm /var/run/mypid.pid; exit 0" EXIT

while [ 1 ]
do

    do_stuff
    sleep 60

done
"

This works - but an attempt to 'kill' it, e.g.

kill `head -1 /var/run/mypid.pid`

Takes up to 60 seconds, before 'sleep' completes, control returns back to 
the shell - which see's the signal, and quits.

Is there a better way of doing this? - i.e. some way the shell can 'pass 
time' but still receive signals in a timely manner?

The only work around I could come up with was to change the 'sleep 60' into 
a loop that does 60 * 1 second sleeps, not ideal though :(

Cheers,

-Karl