gistfile1.txt

#! perl
use strict;
use warnings;
use DBI;
use Sys::SigAction qw(set_sig_handler);

my $h = set_sig_handler(
    'ALRM',
    sub {
        print "fire\n";
    },
);
#$SIG{ALRM} = sub { print "fire\n"; };
my $dbh = DBI->connect('dbi:mysql:test', 'root', '');
alarm(3);
$dbh->do('select sleep(10)');