perl - a half decent datetime ("yyyy_mm_dd_HH_mm_ss.ffffff") method

now.pl

#! /usr/bin/perl

# a Perl script with a "now" method to return a (yyyy_mm_dd_HH_mm_ss.ffffff) timestamp - Linux & Windows filename valid

use strict;
use warnings;

use POSIX; # for "strftime"
use Time::HiRes; # for "Time::HiRes::gettimeofday"
use 5.010;

# return a half decent <datetime> string i.e. "2015_02_02_16_56_40.194733"
sub now
{ 
    my ($seconds, $microseconds) = Time::HiRes::gettimeofday;
    return strftime(q/%Y_%m_%d_%H_%M_%S./, localtime($seconds)) . sprintf("%06d", $microseconds);
}

while(1)
{

  my $t = now();

  say $t;

  # demonstrate file creation based on returned "datetime" format

  my $filename = $t . ".log";
  
  open OUT, ">", "$filename" or die $!; 
  print OUT $t;
  close (OUT);

  sleep(1);

}

exit 0;