Skipping in an FTP stream does not work anymore with v0.9?

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Hi, sorry I've looked all over Google and here but can't find an answer to the problem I am having.

I've used vlc to stream recordings via ftp from my Topfield PVR box for some time and it has always worked well. Recently I upgraded to ubuntu intrepid 8.10 running vlc 0.9.4-1ubuntu3. Now I find that I can't skip ahead in vlc. I get the following messages and then vlc stops (and sometimes hangs).

[00000410] access_ftp access error: cannot retrieve file
[00000408] main input error: INPUT_CONTROL_SET_POSITION(_OFFSET) 0.2% failed

I could skip fine in vlc 0.8 and can still run vlc 0.8.6 on my wife's xp box ok. It seems a new problem with vlc 0.9? Possibly vlc 0.9 uses a different method now to skip forward/backwards in a stream? I expected to find a command line option to enable the old behaviour but can't find one. Anyone have any suggestions?

[Rémi Denis-Courmont]

Looks like the FTP server is returning an error for whatever reason. I need a dump of the FTP session for further debugging.

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Thanks for replying Remi. I switched the ftp server into debug mode and captured the output of a failed run from vlc 0.9.4 on my ubuntu box, and then of a good run from vlc 0.8.6 on my wife's xp box. Both play the stream ok when it starts then I skip ahead and the failure occurs on vlc 0.9.4 but vlc 0.8.6 skips ahead fine. The logs were essentially the same so I'll only reproduce here the salient difference. It seems to me that the new vlc is merely failing to issue a REST ftp command after entering extended passive mode?(!)

Here is the ftpd debug output using vlc 0.9.4 on ubuntu intrepid when I skip ahead in the ftp stream and it fails:

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Finished loop with ret=-1, in_get=0, aborted=1, current @4876800 ftpd-topfield2659: retrieve: Transfer of /DataFiles/Scrubs (2008) - My Waste of Time.rec aborted @4876800 ftpd-topfield2659: <--- 426 ftpd-topfield2659: Transfer aborted. Data connection closed. ftpd-topfield2659: command: ABOR ftpd-topfield2659: <--- 225 ftpd-topfield2659: ABOR command successful. ftpd-topfield2659: Received ABOR ftpd-topfield2659: command: EPSV ftpd-topfield2659: <--- 229 ftpd-topfield2659: Entering Extended Passive Mode (|||3205|) ftpd-topfield2659: command: TYPE I ftpd-topfield2659: <--- 200 ftpd-topfield2659: Type set to I. ftpd-topfield2659: command: RETR DataFiles/Scrubs (2008) - My Waste of Time.rec ftpd-topfield2659: retrieve: /DataFiles/Scrubs (2008) - My Waste of Time.rec @0 retrieve: srcpath=/DataFiles/Scrubs (2008) - My Waste of Time.rec, current=0, ret=-101 tf_cmd_get() returned -101 ftpd-topfield2659: <--- 550 ftpd-topfield2659: Not a file: DataFiles/Scrubs (2008) - My Waste of Time.rec Finished loop with ret=-101, in_get=0, aborted=0, current @0 ftpd-topfield2659: command: ABOR ftpd-topfield2659: <--- 225 ftpd-topfield2659: ABOR command successful. ftpd-topfield2659: Received ABOR ftpd-topfield2659: command: QUIT ftpd-topfield2659: <--- 221 ftpd-topfield2659: Goodbye. .. (and the stream fails)

Here is the ftpd debug output using vlc 0.8.6 on winxp when I skip ahead in the ftp stream and it succeeds:

Code: Select all

Finished loop with ret=-426, in_get=1, aborted=0, current @4212636 ftpd-topfield2737: retrieve: Transfer of /DataFiles/Scrubs (2008) - My Waste of Time.rec aborted @4212636 ftpd-topfield2737: <--- 426 ftpd-topfield2737: Transfer aborted. Data connection closed. ftpd-topfield2737: command: ABOR ftpd-topfield2737: <--- 225 ftpd-topfield2737: ABOR command successful. ftpd-topfield2737: Received ABOR ftpd-topfield2737: command: EPSV ftpd-topfield2737: <--- 229 ftpd-topfield2737: Entering Extended Passive Mode (|||4375|) ftpd-topfield2737: command: TYPE I ftpd-topfield2737: <--- 200 ftpd-topfield2737: Type set to I. ftpd-topfield2737: command: REST 170061063 ftpd-topfield2737: <--- 350 ftpd-topfield2737: Restarting at 170061063. Send STORE or RETRIEVE to initiate transfer. ftpd-topfield2737: command: RETR DataFiles/Scrubs (2008) - My Waste of Time.rec ftpd-topfield2737: retrieve: /DataFiles/Scrubs (2008) - My Waste of Time.rec @170061063 Note: request for data not on 512 byte boundary (170061063 % 512 == 263) retrieve: srcpath=/DataFiles/Scrubs (2008) - My Waste of Time.rec, current=170060800, ret=0 ftpd-topfield2737: <--- 150 ftpd-topfield2737: Opening BINARY mode data connection for 'DataFiles/Scrubs (2008) - My Waste of Time.rec' (2504581120 bytes). Created data connection: fd=8 Trying to write to 64761 bytes to the client Waiting for write for 2 seconds .. (and the stream plays ok from the new position)

I can post the complete logs if you need them.

[Rémi Denis-Courmont]

I cannot reproduce this issue.

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I cannot reproduce this issue.

Can I ask what version you can't reproduce this problem with? I'm running the latest ubuntu intrepid version 0.9.4-1ubuntu3. I can't seem to find a later deb version packaged anywhere - any suggestions?

Do you agree from looking at my logs quoted above that the problem seems to be that vlc is simply failing to issue a REST command?

[Rémi Denis-Courmont]

Nope. The FTP plugin appears to seek fine. It's likely a bug in the file format handler. I cannot help with that.

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Ok, 2 months later ...

Not being able to use vlc anymore is killing me! Please, can somebody please suggest where I can go for help next?

I installed vlc 0.8.6i (last of the 0.8 series) in a virtualbox xp machine and proved that it works fine. I can skip wherever I like in the ftp stream and it always plays fine from the new position. I installed vlc 0.9.2 (first of the 0.9 series) and it hangs immediately when I move the slider bar. It will play fine to that point and I can pause and unpause or stop and play just fine. I reproduced this behaviour on a real windows xp machine and on my ubuntu linux box so it seems the bug is generic to the 0.8 to 0.9 vlc changes. Same ftp server/device, same playing file.

Remi - can you suggest somebody/somewhere else where I can post for help?

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For the next punter who may come along with this or a similar problem ....

I debugged the connection between the newer vlc and the ftp server and found that the newer vlc does not close the socket down gracefully on a skip so the ftp-server was failing to execute some cleanup logic on the device transfer before initiating the next transfer. I have the source code for the ftpd-topfield so I changed ftpd.c to make sure it cleans up the transfer no matter how the socket is broken and this fixes the problem. I have sent the patch to the maintainer of ftpd-topfield.