#!/usr/local/bin/perl -s
#
# replace.pl
#
# Replace the old pattern with a new pattern in given source file!
# Just edit the first line, if your perl executable sits on different    
# dir. You can find out the location with "which perl" command. 

# Run "replace.pl -h" to see more options.
#
# Last modified:	8/7/96
# Author: Bekman Stas   <c0409532@techst02.technion.ac.il>
#                       <sbekman@iil.intel.com>

$0 =~ s/^.*\///;        # cut the basename of the command

# Diagnostic part...
if ($#ARGV<2 || $h) {
die "\nUsage: 
\t $0 [-options] old_pattern new_pattern original_file(s) 
options:
   -h  		You read me now
   -no_bak	Don't backup the original file
   -no_glob     If you want to replace only first occurence in each line
   -no_sens	Case insensitive replace
  
   old_pattern	single pattern without quotes or 'any exact sub sentence'
   new_pattern  the same as old_pattern\n"
}

# Real program...
# Remove the patterns from @ARGV, leave only filenames
# Note: options stripped from @ARGV by "perl -s" flag !!! So we have only filenames 
$old=(shift @ARGV);
$new=(shift @ARGV);

# Store the original files' modes (Must do! Because of open(Bla,">foo") )
foreach (@ARGV) {
$modes{$_}=(stat)[2];      
}
while (<>){
    if ($ARGV ne $oldargv){
    	if (!$no_bak) {rename($ARGV, $ARGV . '.bak');}
    	open (ARGVOUT, ">$ARGV") || die "Can't open $ARGV[0]: $!\n"; 
    	select(ARGVOUT);
    	$oldargv= $ARGV;
    }
   (!$no_glob) && (!$no_sens) && (s/$old/$new/og)  && next;
   (!$no_glob) && ($no_sens)  && (s/$old/$new/ogi) && next;
   ($no_glob)  && (!$no_sens) && (s/$old/$new/o)   && next; 
   ($no_glob)  && ($no_sens)  && (s/$old/$new/oi)  && next;

} continue { 
	print;		# this prints to the original filename
}

close(ARGVOUT);
select(STDOUT);



# Restore the original files' modes (Must do! Because of open(Bla,">foo") )
foreach (keys %modes) {
chmod $modes{$_},$_;
}