Missing 4k bug

WinSCP 4.2.2 Build 480
Windows XP Pro SP3 5.1.2600

Session protocol = SSH-2
SSH implementation = 2.3.1 F-SECURE SSH
Encryption algorithm = blowfish
Compression = No
File transfer protocol = SFTP-2
Using GUI

Files transferred using WinSCP 4.2.2 occasionally are missing the last 4k.

Steps to reproduce: This happens occasionally, I have not been able to predict it.
1) Use GUI, enter the hostname/ip to remote server
2) Enter username/password when prompted
3) Drag and drop remote file to local drive via the winscp gui. From the right pane to the left pane.
4) Wait for transfer to complete.
5) Find a file that may be 4k smaller than the file on the remote server.

I used a visual binary diff program and found the last 4k were missing. Curiously there is also some data in the middle of the file that is different as well, but then matches up until the last 4k. However downloading the file again after a restart on the system running winscp resulted in a working file, that was complete.

I just found the logging option and will keep it enabled so that I can provide (hopefully) more helpful information. What logging level should I use?

boarsoup wrote:

I just found the logging option and will keep it enabled so that I can provide (hopefully) more helpful information. What logging level should I use?

The more details the better. Though you may not be able to reproduce the problem with too detailed logging. Try it and see.

This may be unrelated. I had logging running this time(unfortunately the log got lost when the session died).

It lost connection to the server and kept attempting to reconnect. Eventually I told it just to stop, at this point the log window disappeared and a windows message box appeared saying, "Assertion failed: xdrPtr && xdrPtr == *xdrLPP, file xx.cpp, line 2233" followed by, "Abnormal program termination" and then it terminated.

The program has been kept open for a few days, but I didn't notice a memory leak.

boarsoup2 wrote:

This may be unrelated. I had logging running this time(unfortunately the log got lost when the session died).

It lost connection to the server and kept attempting to reconnect. Eventually I told it just to stop, at this point the log window disappeared and a windows message box appeared saying, "Assertion failed: xdrPtr && xdrPtr == *xdrLPP, file xx.cpp, line 2233" followed by, "Abnormal program termination" and then it terminated.

The program has been kept open for a few days, but I didn't notice a memory leak.

Are you able to reproduce the problem?

The issue I had with the missing 4k turned out to be some legacy fortran code that doesn't always close files, but that people claimed was bug-free.

Thanks for your help!