open(FILE,"+<tabs.txt") or die "Couldn't open tabs.txt: $!";
my @file = <FILE>; 
seek(FILE,0,0);
foreach(@file) {
     s/\t/,/g;
     print FILE $_;
}
close(FILE);

##</code><code>##

open(FILE,"+<tabs.txt") or die "Couldn't open tabs.txt: $!";
my @file = <FILE>; 
seek(FILE,0,0);
 foreach(@file) {
     chomp();
     my $line = "";
     my(@values) = split(/\,/,$_);
     foreach my $value(@values) {
          $value = "\"$value\"" if $value !~ /^\".*?\"$/;
          $line .= "$value,";
     }
     chop($line);   
     print FILE "$line\n";
} 
close(FILE);