alarm 900;  #send alarm after 900 sec
$SIG{ALRM} = \&alarm_fnct;

# Here should be the code of your allways running server

sub alarm_fnct {
 print "Get alarm Signal";
 ...
 alarm 900; ## and again call alarm after 900 sec.
}

##</code><code>##

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--the good, the bad and the physi--
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