[Patches] urllib NLST patch

[Fredrik Lundh]

from the newsgroup:

Oleg Broytmann <phd@phd.russ.ru> wrote:
> What am I doing wrong? And how to use urllib to get files by FTP?
>
> fname, headers =3D =
urllib.urlretrieve("ftp://koobera.math.uic.edu/www/djb.html")
>
> IOError: [Errno ftp error] 426 Transmission failure: not a directory

background: urllib issues an NLST command to make sure
the file exists, before starting the download.  however,
RFC959 doesn't necessarily allow this:

    [NLST] causes a directory listing to be sent from
    server to user site.  The pathname should specify a
    directory or other system-specific file group descriptor;
    a null argument implies the current directory.

most FTP servers seem to treat NLST commands as
an ordinary "ls -l", but this one doesn't.

I'm pretty sure the only reasonable solution is to remove
the offending code from urllib...

-- end of posting

and here's a patch that does exactly that.  cannot see
any problems with it, but on the other hand, I'm pretty
sure the NLST call was added for a reason.

please discuss before applying.

*** urllib.py.bak Wed Feb 02 00:36:53 2000
--- urllib.py Fri Feb 11 15:53:51 2000
***************
*** 643,655 ****
              self.ftp.voidcmd(cmd)
          conn =3D None
          if file and not isdir:
-             # Use nlst to see if the file exists at all
-             try:
-                 self.ftp.nlst(file)
-             except ftplib.error_perm, reason:
-                 raise IOError, ('ftp error', reason), =
sys.exc_info()[2]
-             # Restore the transfer mode!
-             self.ftp.voidcmd(cmd)
              # Try to retrieve as a file
              try:
                  cmd =3D 'RETR ' + file
--- 643,648 ----

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