P4VFS and WSL2 9p filesystem

[lweiner-spirent]

I have used P4VFS on Windows to sync to the latest version of my project (p4vfs sync ...#head). However, I'm using VSCode running under WSL2/Ubuntu-20.04 to edit files. When I try to access the files using VSCode or Ubuntu command line, then I only see zeros in the file:

If I use a native Windows program to read the file, then I can see the actual contents of the file in WSL...

$ od -tx1 SourceCode.cc
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0213720 00 00 00 00 00 00 00 00 00 00 00
0213733

$ /mnt/c/windows/system32/cmd.exe <<< "type sourceCode.cc" &> /dev/null
$ od -tx1 SourceCode.cc
0000000  2f  2f  20  24  49  64  3a  20  ...
...
0213720  53  74  61  74  65  3b  0a  7d  0a 
0213733

Is it possible to make this run seamlessly under WSL? (i.e. without the need to use a windows native program to trigger P4VFS)?

[jessk-msft]

Thanks for calling this out. It looks like the filter driver is being skipped for non-windows-native processes. In this case you're seeing zeros which have padded out the SPARSE stream of the P4VFS placeholder file. I actually haven't considered WSL until now, but it would be great to properly support it.

I'll dig around to see how our most common filters behave with WSL.
Regards
-Jess