Re: Invasion on FTP!

From: Alun Jones (alun@texis.com)
Date: 10/03/02 

From: alun@texis.com (Alun Jones)
Date: Thu, 03 Oct 2002 16:27:22 GMT

In article <VJ5FhqlaCHA.1700@cpmsftngxa06>, TimGreene@online.microsoft.com
(Tim Greene) wrote:
>The reason these files can't be renamed is because they're uploaded and
>named with Unix names that are not completely understood by our file
>system. Because of this, they're not easy or sometimes not possible to
>delete.

I don't know that it has anything to do with Unix - the file system allows the
use of characters that are somewhat difficult to replicate or tell apart from
others.

For example, if you do the following:

dir > "foo bar"

You'd expect to create a file called "foo bar" that you can delete as "foo
bar". Now try that command, but instead of typing the space between foo and
bar using the space bar, hold down the ALT key, and on the numeric keypad, hit
255 - then let go of the ALT key.

It looks like a space, but it isn't. _Some_ commands think it's a space -
type "del foo" and hit TAB for the file completion. The completion comes back
as "del foo bar", and when you hit return, you get "Could not find C:\foo".
But enclose it in quotes, and type it with ALT-255 again, and you'll be able
to delete the file.

Perhaps this user's "folder with no name" actually uses that 255 character.

For instance, I create a file called " " (that's the 255 character, not a
space, but this newsreader may have translated it here :-)), and I do the
following commands:

dir /b > foo
debug foo

When I type the 'd' command, to display hexadecimal characters, I get the
following (this is partial output):

>debug foo
-d
0B35:0100 44 65 73 6B 74 6F 70 0D-0A 46 61 76 6F 72 69 74 Desktop..Favorit
0B35:0110 65 73 0D 0A 66 6F 6F 0D-0A 4D 79 20 44 6F 63 75 es..foo..My Docu
0B35:0120 6D 65 6E 74 73 0D 0A 53-74 61 72 74 20 4D 65 6E ments..Start Men
0B35:0130 75 0D 0A FF 0D 0A u.....

As you can see, from the end of the list there, there's the "u" of "Start
Menu", followed by carriage return and line feed (0d 0a in hex), then the 255
character (FF in hex).

Piping a directory listing into a program that shows you what exact characters
are present may show you what characters to type to get rid of the file. I'm
sure it'd be useful if someone at Microsoft could compile a list of the sort
of file characters that these people use in order to confuse site owners.

Alun.
~~~~

[Please don't email posters, if a Usenet response is appropriate.] 

-- 
Texas Imperial Software   | Try WFTPD, the Windows FTP Server. Find us at
1602 Harvest Moon Place   | http://www.wftpd.com or email alun@texis.com
Cedar Park TX 78613-1419  | VISA/MC accepted.  NT-based sites, be sure to
Fax/Voice +1(512)258-9858 | read details of WFTPD Pro for XP/2000/NT.

Relevant Pages

  • Re: Splitting a string into characters portably
    ... characters. ... Here's a portable 2 command equivalent of GAWK's ability to split with "": ... Doesn't this work for the K&R awk (except maybe for the default ...
    (comp.lang.awk)
  • [ANN] main-2.6.0
    ... a class factory and dsl for generating command line programs real ... option 'foo' ... improved auto usage generation when arity is used with arguments ... cast:int ...
    (comp.lang.ruby)
  • [ANN] main-2.8.3
    ... a class factory and dsl for generating command line programs real ... def runputs 'installing...' ... and auto-generation of usage messages can really ... int(foo): the cast is int, ...
    (comp.lang.ruby)
  • [ANN] main-2.2.0
    ... a class factory and dsl for generating command line programs real quick ... def runputs 'installing...' ... and auto-generation of usage messages can really streamline ... int(foo): the cast is int, ...
    (comp.lang.ruby)
  • [ANN] main-2.5.0
    ... a class factory and dsl for generating command line programs real ... def runputs 'installing...' ... and auto-generation of usage messages can ... int(foo): the cast is int, ...
    (comp.lang.ruby)