#!/usr/bin/perl
use warnings; use strict;

use String::Scanf qw();

sub scanf {
  my $pat = String::Scanf::format_to_re(shift);
  my $input = shift;
  return $input =~ /^${pat}$/;
}

my $format = "Input queue: %d/%d/%d/%d (size/max/drops/flushes); Total output drops: %d";
my $input = "Input queue: 0/75/0/39 (size/max/drops/flushes); Total output drops: 19845805";

if (my ($size,$max,$drops,$flush,$total) = scanf($format, $input)) {
  warn "Gotcha: size=$size, max=$max,drops=$drops,flush=$flush,total=$total";
}