alarm would be one way: 

    my $OLD_SIG = $SIG{ALRM} if $SIG{ALRM};
    $SIG{ALRM} = sub { die "timeout" };

    eval {
        alarm( 30 );
        # do what needs to be done
        alarm( 0 );
    };

    if( $@ ) {
        if( $@ =~ /^timeout$/ ) {
            print STDERR "A timeout occurred";
            alarm(0);
        } else {
            print STDERR "Some other error occurred";
        }
    }

    $SIG{ALRM} = $OLD_SIG if $OLD_SIG;

[download]

-derby

update: Whoa! Mis-read your question as not more than 30 seconds. I'm not sure why you would want it to run for at least 30 seconds but you could sleep.

In reply to Re: Setting the max execution time? by derby
in thread Setting the max execution time? by deepy

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