use strict;
require "asm/param.ph";

open UPTIME, "</proc/uptime";

my @up = split('\s+', <UPTIME>);

close UPTIME;

my $pid = shift or die "need pid";

open STAT, "</proc/$pid/stat";

my @stat = split('\s+', <STAT>);

close STAT;

my $total_time = $stat[13] + $stat[14];
my $include_dead_children = 1;
if ($include_dead_children) {
   $total_time += $stat[15] + $stat[16];
}
print $stat[21], "\n";

my $start_time = $stat[21];

my $seconds = $up[0] - $start_time / HZ();

my $pcpu;
if($seconds) {
    $pcpu = ($total_time * 100 / HZ()) / $seconds;
}

print "start_time $start_time\n";
printf("%%CPU %2.2g\n", $pcpu);
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