#!/usr/bin/perl -w
##
##   Perl equivalent of the popular dos2unix utility:
##
##   Convert DOS line endings to Unix line endings:
##   works in bulk, safely updates files in place.
##
my  ($filename, $line, $count);
$count = 0;

#   If no arguments, print an error message
if( $#ARGV < 0 ) {
    print "Usage: $0 filenames\n";
    print ";Replace DOS line endings with Unix line endings\n";
    exit(5);
}

                #   Loop through each given filename
foreach $filename (@ARGV)
{
   if( -e "$filename.bak" ) {
      printf "Skipping $filename.bak - it already exists\n";
   }
   elsif(!( -f $filename && -r $filename && -w $filename  )) {
      printf "Skipping $filename - not a regular writable file\n";
   }
   else {
      rename("$filename","$filename.bak");
      open INPUT, "$filename.bak";
      open OUTPUT, ">$filename";
      while( <INPUT> ) {
         s/\r\n$/\n/;     # convert CR LF to LF
         print OUTPUT $_;
      }
      close INPUT;
      close OUTPUT;
     unlink("$filename.bak");
     $count++;
   }
}
printf "Processed $count files.\n";