use Getopt::Std;
use vars qw'$opt_f $opt_P $VERSION';
$VERSION = 0.08;

unless( @ARGV ){
    print<<EOUsage;
usage: vfgrep [-P] -f PATTERNS [FILE]

-P prune patterns on match, if a pattern will only match once per file
   this can speed up execution by discarding the pattern once it has matched.

EOUsage
    exit;
}
getopts('Pf:');

die("vfgrep requires a pattern file\n") unless defined $opt_f;
open(PAT, $opt_f) or die("Error opening pattern file '$opt_f': $!\n");

#Strip any sort of EOL garbage
#Also pre-compile the regexp for a major performance boost
my @PAT = map{ y/\r\n//d; qr/$_/ } <PAT>;
close(PAT);

if( $opt_P ){
    REC: while(<>){
	#Premature optimization?
	last unless scalar @PAT;

	foreach my $i (0 .. $#PAT ){
	    splice(@PAT, $i, 1) && next REC if /$PAT[$i]/;
	}
	print;
    }
    print <> unless eof; #Pairs with last unless
}
else{
  REC: while(<>){
      foreach my $pattern ( @PAT ){
	  next REC if /$pattern/;
      }
      print;
  }
}
__END__
Todo: mmap?