UNC, ftp, FileSystemWatcher

[John Bailo]

I've posted parts of problems in other posts, but I thought I'd
consolidate my questions because I still don't have a solution.


Problem:

I want to use the creation of a file on a remote ftp site (running Unix)
as a trigger for other processes to start.


Platform:

Windows 2000 server running .Net
Remote ftp site running unix


Thoughts:

I thought that if I could somehow access an ftp site with UNC or map a
drive letter to the ftp site, I could use the FileSystemWatcher class to
monitor the ftp site.


Explorations:

In Windows Server 2000, I have not found any way yet to mount an ftp
site with a drive letter. I have not found a way to mount an ftp site
as a drive letter.

One poster recommended writing a network redirector -- however I don't
know if my skills are up to it...or if it's the right path. I would
like some verification...and I want to make sure there is not an easier
way before building such a thing in .net

I would prefer not to use any 3rd party windows software that

(a) costs real money or
(b) does not provide source code.

 

[Stelrad Doulton]

I would forget the FileSystemWatcher idea. All it does it wrap some Windows
specific API's, it just ain't going to work. If you can't write code for the
UNIX box I think you are left with polling for the change.

 

[John Bailo]

I would forget the FileSystemWatcher idea. All it does it wrap some Windows
specific API's, it just ain't going to work. If you can't write code for the
UNIX box I think you are left with polling for the change.

Thanks, that's /exactly/ what I needed to know.

I'll go with a loop and put in a delay to adjust if the file is still
open or being created...unless there's a way to examine file status from
..Net.

 

[Stelrad Doulton]

FTP support is in .NET 2.0, until then you will need a 3rd party
implementation. There are lots about. You want one that exposes the last
modified property of the file as this one does:
http://www.enterprisedt.com/products/edtftpnet/doc/api/index.html

 

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

I'll go with a loop and put in a delay to adjust if the file is still open
or being created...unless there's a way to examine file status from .Net.

If you have access to the process that create the file you could ask to
create another file with the same name but with a different extension, this
"flag" file is created when the data file is ready to be downloaded.


cheers,

 

[John Bailo]

Hi,





If you have access to the process that create the file you could ask to
create another file with the same name but with a different extension, this
"flag" file is created when the data file is ready to be downloaded.


cheers,

Good idea...unfortunately, this is basically a 'read only' situation
from me as the orgin is a client's ftp site.

 

[John Bailo]

Stelrad -- this is perfect! It's GNU licensed...

" edtFTPnet is the first choice of .NET developers worldwide for
incorporating FTP functionality into their applications.

edtFTPnet is Open Source, licensed under the LGPL, the GNU Lesser
General Public License.

This means you can freely embed edtFTPnet into your commercial .NET
applications, subject to the normal LGPL restrictions. Unrestricted
(non-GPL) source licenses can be also be purchased.

edtFTPnet/PRO provides SOCKS proxy support and secure FTP capabilities
via FTPS. "

 

[John Bailo]

Hi,





If you have access to the process that create the file you could ask to
create another file with the same name but with a different extension, this
"flag" file is created when the data file is ready to be downloaded.

My current implementation is this:

I loop through all the files on the ftp server, and I do a
!File.Exists() on my local directory. If not, then I download it.

I like Stelrad's suggestion of employing add on libaries that let me
view the LastModified, so I can can look for files that appeared since
the last runtime -- that is more elegant because I don't need to
maintain an archive of all the files on my local folder.

I also looked at a tool called WebDrive. This is a shareware component
that will take and ftp site and let you map a drive letter to it.
Unfortunately the current version won't support FileSystemWatcher -
however, their support department tells me the 7.0 version, to be
released this summer, will...and that will make it a very good tool to have!

Then of course there's Net 2.0 -- I need to plow through those docs as
well...