#!/usr/bin/perl
# @(#) cutgrep V1.0 cuts the regular expression from the file
# Author: Shankar Chakkere (shankara@erols.com)
# Date: 25 Nov 1996
# Status: Working
# Abstract: This script will cut the regular expression from each line of the
#           file
# Usage: cutgrep regexp filename
# History: Mar 02 1998
# Added option -v to verify which portion will be cut by printing both the
# unmodified line and the modified line. The modified line will be enclosed
# within $encloser
# Copyright (C) 1999 Shankar Chakkere
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Visit http://www.fsf.org for more information

########################################################################

$debug = 0;

$encloser = '**';

($#ARGV < 0 ) && &usage; #     $#ARGV -1 when no command line parameter

$verify = 0;

while ($ARGV[0] =~ m/^-/)
 {                          
    $_= shift(@ARGV);
                                
    print "$_\n" if $debug;
    s/^-//;
        while (s/^.//)
         {                             
            if ($& eq 'v')
              {                         
                $verify = 1;                        
               }
           else 
                {                                 
                &badusage("Unknown option \-$&\n");
                }                                        
          }                                    
  } #while ($ARGV[0] =~ m/^-/)


$pattern = $ARGV[0];

open(FILE, $ARGV[1]) || die "Can't open input file : $ARGV[0] . $!";

while (<FILE>)
{
   chop($_);
   if( /$pattern/)
     {
      if( $verify )
        {
         print "$_\n" if $verify;
         print "$encloser $ $ $encloser\n";   # $` = line before match ,
                                                # $& = pattern matched
        }
      else
        {
         print "$ $\n";             # $` = line before match ,
                                      # $& = pattern matched
                                      # $' = rest of line after match
                                      # space inbetween$` and $' is needed
        }
     }
   else                               # print all line if no match found
     {
       print "$_\n";
     }
}
close FILE;

sub usage { 
    die <<EOF
$0 will cut the regular expression from each line of the file
       Usage: $0 [-v] perl-regular-expression file
       Where:
         -v[erify] will print the line modified below the line which
          was modified within $encloser $encloser
EOF
}

sub badusage
 {
    print STDERR $_[0];           
    &usage;                       
    exit 1;                       
}