#!/usr/bin/perl -w

my $method = shift or usage();
if($method eq 'tail'){
    $0 = 'tail';
    tail_inf();
} elsif($method eq 'nontail'){
    $0 = 'nontail';
    nontail_inf();
} else {
    usage();
}

sub tail_inf{
    L1: print_resources(); goto L2;
    L2: goto L1;
}

sub nontail_inf{
    goto &T1;
    sub T1{ print_resources(); goto &T2; }
    sub T2{ goto &T1; }
}

{
    my $i=0;
    my $j=0;
    sub print_resources{
        $i++;
        $i = $i % 100000;
        return unless $i == 0;
        my @lines = grep {$_ =~ /\s+(\d+)/ and $1 eq $$}  `ps u`;
        print @lines;
        $j++;
        exit if $j == 10;
    }
}

sub usage{
    print "Usage: $0 tail|nontail\n";
    exit(-1);
}