use strict;
use warnings;
use POSIX qw(strftime);
my $modtime_seconds = ( stat($file) )[9];
$modtime_seconds = $modtime_seconds - 86400;
my $modtime = ( ! defined ($modtime_seconds) ) 
    ? "null" 
    : POSIX::strftime( "%B %d", $modtime_seconds, 0, 0, 0, 0, 0, 0, 0, 0 );