Active Passive Modes

[John Schexnaydre]

I have been using Don's excellent FTP functions and they work well.

I have come to an issue where an FTP server I need to work with does not support Passive mode only Active.

Can Don's FTP functions be changed to support Active mode?

If not has anyone else faced this issue?

Suggestions?


Thanks,

John Schexnaydre

[Roger Garstang]

Anything is possible if you have the source. You can look up the FTP RFC (Files are available for download here too) and see the specs on how it works and rewrite the function. It is mostly a difference on who connects to who for the data channel, everything else should work the same. I wrote my own HTTP Web Server and an app to connect to a piece of hardware by FTP this very same way just by reading RFCs. It helps to have apps like WireShark and stuff too to watch packets and see what goes on. Some developers don't read very well and end up making a server that doesn't follow specs, so you have to figure out what they did wrong and allow for it, etc.

Also, I think I looked at his or someone's functions for ideas too and there was a switch to change modes...

[Michael Mattias]

I recently posted some FTP access code which shows active and passive connections.

Let me see if I can find it...here it is...
WinInet FTP Upload (Overwrite or Append) Demo 3-10-08

MCM

[John Schexnaydre]

Active Passive Modes

Thanks!

I had already started looking at Wininet. Seems like a good route to go.

I still may take a look at how the FTP PORT command works and see if I can get that to work in Don's FTP functions. That would be the safe way to go as I would have less new code to write and test.

Many thanks again!

John

[John Schexnaydre]

In working with the WinInet Functions, the FTPPutFile function attemps
Passive Mode which I cannot use.

I see a Flag to Set Passive Mode, but none to set Active or fall over to Active if Passive mode fails.

Anyone knows if/how FTPPutFile can be set to Active mode?

Thanks

John Schexnaydre

[John McWilliams]

In working with the WinInet Functions, the FTPPutFile function attemps
Passive Mode which I cannot use.

I see a Flag to Set Passive Mode, but none to set Active or fall over to Active if Passive mode fails.

Anyone knows if/how FTPPutFile can be set to Active mode?

Thanks

John Schexnaydre

Not to be obvious, but try setting "SetPassiveMode" to %FALSE

[John McWilliams]

The above post was a bit glib. I apologize. The Help file states that

&H80000000 ' Long-integer constant (signed)

The Binary equviliant for that is "1" or TRUE. Try changing the variable to &H00000000 or FALSE.

Again excuse my glibness, it was a long and arduous day.

[John Schexnaydre]

Thanks!

Tried with only &H00000000 and call still atemps to use Passive.

[Mike Stefanik]

I don't know if you're interested in using a commercial library or not, but if you don't want to thump your head against WinInet, our SocketTools Library Edition product supports both active and passive FTP transfers, and it's a heck of a lot easier to use (in my admittedly biased opinion). If you're interested, shoot me a PM and I can get you pointed in the right direction.

[John Schexnaydre]

Thanks All.

I got a reprieve. The test server at the 3rd party doesn't support Passive.

Our customer received his server and it does support Passive.

So off the hook today, but I'm sure this will come up in the future so I plan
to continue looking to upgrade my FTP functions to support Active and Passive modes.

Some quick searches for WinInet FTPPutFile function shows that it does't support Active mode. But if so then why have a flag to set Passive mode?
Strange.

John Schexnaydre

[John McWilliams]

Iteresting, indeed....

http://cboard.cprogramming.com/showthread.php?t=49993

[John Schexnaydre]

Strange, my last reply disappeared!

Above I had already tried 0 with no success.

Thanks
John

[John McWilliams]

Strange, my last reply disappeared!

Above I had already tried 0 with no success.

Thanks
John

I know you did that is why the response from the other forum was so strange. It failed for you but worked for him.... very strange.

[John Schexnaydre]

And it appears the answer is:

%INTERNET_OPEN_TYPE_DIRECT=1

[John McWilliams]

And it appears the answer is:

%INTERNET_OPEN_TYPE_DIRECT=1

Did that fix it? What were you using originally? The original code I posted had %INTERNET_OPEN_TYPE_DIRECT defined as &H1

Later:
Never mind I just got it. You're opening not as %INTERNET_OPEN_TYPE_PRECONFIG but as %INTERNET_OPEN_TYPE_DIRECT and setting the %INTERNET_FLAG_PASSIVE to 0 (Zero).

[John Schexnaydre]

Correct. It would seem you would need to try Active mode and if that fails reconnect and try again with Direct.

Here is the link to a major find in my searching:

http://www.codenewsgroups.net/group/microsoft.public.vb.general.discussion/topic6364.aspx

Some good utility functions as well like the error code to text message, etc.

Also I wonder if something like this would work?

INTERNET_OPEN_TYPE_DIRECT OR INTERNET_FLAG_PASSIVE

[John Schexnaydre]

Also I wonder if something like this would work?

INTERNET_OPEN_TYPE_DIRECT OR INTERNET_FLAG_PASSIVE

Didn't work for me.

[John McWilliams]

I'm on vacation right now so I'm not exactly in "code mode" I will take a look at the link and see what's going on though. Thanks for sticking with the "problem".