use strict;
use warnings;

my $path = $ARGV[0];

exit unless $path;

if ( -w $path ) {
   print "'$path' is writeable\n";
   eval {
      open my $fh, '>', "$path/foo.txt" or die $!;
      print $fh "foo\n";
      close $fh;
   };
   if ( $@ ) {
      print "\twrite failed: '$@'\n";
   }
   else {
      print "\twrite succeeded\n";
      unlink "$path/foo.txt" or die $!;
   }
}
else {
   print "'$path' is not writeable\n";
   eval {
      open my $fh, '>', "$path/foo.txt" or die $!;
      print $fh "foo\n";
      close $fh;
   };
   if ( $@ ) {
      print "\twrite failed: '$@'\n";
   }
   else {
      print "\twrite succeeded\n";
      unlink "$path/foo.txt" or die $!;
   }
}

##</code><code>##

perl is_path_writeable.pl folder\ with\ spaces
'folder with spaces/' is writeable
        write failed: 'Operation not permitted at is_path_writeable.pl line 11.
'

##</code><code>##

perl is_path_writeable.pl "C:\Documents and Settings\bke\My Documents"
'C:\Documents and Settings\bke\My Documents' is not writeable
        write succeeded