sub my_string_index($\@) {
    my ($symkey, $symkeys)=@_;
    my $index=-1;
    for ($index=0;$index<=$#$symkeys; ++$index) {
        if ($symkeys->[$index] eq $symkey) { return $index; }
    }
    return -1;
}

##</code><code>##

@cursor_keys = qw(<Up> <Down> <Left> <Right>);
$keyname_to_find='<Down>';
my_string_index $keyname_to_find, @cursor_keys;

##</code><code>##

# skeleton file read & write functions...
sub readfile {  my ($array_p)=@_;  @$array_p=<>;}
sub save_file {
  my ($array_p)=@_;  foreach (@$array_p) { print $_;  }
}
# (above dummy routines will be changed later)
### main program ###
# first open file
readfile(\@cur_file);         #will put file into specified array
#update code

#delete blank comment lines and blank lines
@mynewfile=grep ( !/^#?\s*$/, @cur_file);

#save results back in file
save_file(\@mynewfile);   #will save array back to file