#!perl -w
use strict;

my $dir      = 'C:/somedir/';
my $file     = 'C:/otherdir/t.htm';
my $criteria = qr/\.html?$/;

my $num = 0;

opendir DIR, $dir or die "Could not open '$dir': $!";
my @files = readdir DIR;
closedir DIR;

open INFILE, '<', $file or die "Could not open '$file': $!";
# binmode INFILE; # for non-text file uncomment this line
for (@files) {
   next unless -f $dir . $_; # skip non-files
   next unless /$criteria/;  # skip files not matching RegEx
   seek INFILE, 0, 0;
   open OUTFILE, '>', $dir . $_ or die "Could not open '$_' for output: $!";
   # binmode OUTFILE; # for non-text files uncomment this line
   print "Copying '$_'...\n";
   ++$num;
   print OUTFILE while (<INFILE>);
   close OUTFILE;
}
close INFILE;

print "Done.\nCopied $num files.";