I like the alarm idea. But using threads would be even better. 
use strict;

use Time::HiRes qw ( alarm time usleep sleep);

our $starttime;
our $lasttime;
our $linecount = 0;
our $lastlinecount = 0;

$SIG{ALRM} = sub {
        my $now = time;
        printf "\rline %d %8.1f avg lines per second %8.1f lines per s
+econd",
          $linecount, $linecount/($now - $starttime),
          ($linecount - $lastlinecount) 
            / ($now - $lasttime);
        $lasttime = time();
        $lastlinecount = $linecount;
    };

alarm(1, .5);
$| = 1;

$lasttime = $starttime = time();
while (1) {
    $linecount++;
    last if $linecount > 9999;
    usleep(0.001);
};
print "\n";
alarm(0);
$SIG{ALRM} = undef;

[download]
-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to Re: Live operations-per-second counter by gam3
in thread Live operations-per-second counter by acidmax

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