#!/usr/bin/perl
my $word = shift;
while (<>) {
    s/\Q$word\E/\e[31m$word\e[0m/g;
    print;
}

__END__

#!/usr/bin/perl -s
# jac

$usage = "
Usage: highlight [-h -l -u -i] EXPR1 EXPR2 ...

Options:
  -h  display this help and exit
  -i  insensite search
  -l  lower case letters of expressions
  -u  upper case letter of expressions

see perldoc highlight for more information

";

if ($h)
{
  print $usage;
  exit
}

if ($l && $u)
{
  die("you can only choose one of -u and -l.\n")
}

@e = shift || die("at least one expression is needed.\n");

while ($e = shift)
{
  push @e, $e
}

unless ($u || $l)
{
  $e1 = ">>>";
  $e2 = "<<<"
}

$e = join ("|", @e);

while (<>)
{
  if ($i)
  {
    s!$e!
      $t = $&;
      if ($u) {$t =~ tr/a-záàãâäéèêëíìîïóòõôöúùûüç/A-ZÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÔÕÖÚÙÛÜÇ/}
      if ($l) {$t =~ tr/A-ZÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÔÕÖÚÙÛÜÇ/a-záàãâäéèêëíìîïóòõôöúùûüç/}
      "${e1}${t}$e2"
      !gei;
  }
  else
  {
    s!$e!
      $t = $&;
      if ($u) {$t =~ tr/a-záàãâäéèêëíìîïóòõôöúùûüç/A-ZÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÔÕÖÚÙÛÜÇ/}
      if ($l) {$t =~ tr/A-ZÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÔÕÖÚÙÛÜÇ/a-záàãâäéèêëíìîïóòõôöúùûüç/}
      "${e1}${t}$e2"
      !ge
  }
  print
}

__END__

=head1 NAME

highlight - highlights expressions

=head1 SYNOPSIS

highlight [OPTIONS] EXPR1 EXPR2 ...

=head1 DESCRIPTION

highlight marks matches of given expressions

=head1 USAGE

highlight [ -h | -u | -l ] [ -i ] EXPR1 EXPR2 ...

=head1 OPTIONS

=head2 -h

displays an help text

=head2 -i

insensitive search

=head2 -l

highlighting is done by lower casing all letters inside matches

=head2 -u

highlighting is done by upper casing all letters inside matches

=head1 BUG REPORT / COMMENTS / SUGESTIONS

all of this should be send to the author, at his current e-mail address (see section below).

=head1 AUTHOR

Jose' Alves de Castro <jac@natura.di.uminho.pt>

=cut