FUSE: Restrictions/Limitations for UNC-Path option?

[infeo]

Hey,

the FUSE api of WinFSP offers theVolumePrefix option, to mount the filesystem as a network drive, see

winfsp/src/dll/fuse/fuse.c

Lines 103 to 106 in c61679a

	FUSE_OPT_KEY("UNC=", 'U'),
	FUSE_OPT_KEY("--UNC=", 'U'),
	FUSE_OPT_KEY("VolumePrefix=", 'U'),
	FUSE_OPT_KEY("--VolumePrefix=", 'U'),

and

winfsp/src/dll/fuse/fuse.c

Lines 640 to 641 in 6fb7255

	" -o VolumePrefix=UNC set UNC prefix (/Server/Share)\n"
	" --VolumePrefix=UNC set UNC prefix (\\Server\\Share)\n"

Mounting the filesystem, it is then accessible over the assigned drive letter and the UNC path. According to the help output, the path should be of form /server/share. If for the "share" part a path with more than one section is used, the filesystem is still mounted and accessible via its assigned drive letter, but you cannot access it anymore via its UNC path.

For example, if I mount the filesystem with option -oVolumePrefix=/localhost/myShare/foobar, i cannot access the filesystem with \\localhost\myShare\foobar.

[billziss-gh]

When choosing UNC paths you should avoid using prefixes that are already meaningful. The name localhost already has a well defined meaning, so it is likely that one of the built-in network redirectors is attempting to handle it.

Use a name like /cryptomator/myShare/foobar and it should work.

[infeo]

I tried this with the memfs-fuse3 filesystem: .\memfs-fuse3-x64.exe -ouid=-1 -ogid=-1 -oUNC=/some/test/path

Changing director to the network share failed:

PS C:\Users\Arbeit> cd \\some\test\path
Set-Location: The network path was not found. : '\\some\test'

[infeo]

Also ensured, that WinFsp is the first in the network provider order

[billziss-gh]

I cannot test this right now, but try mounting the file system as a drive as well (i.e. add an X: at the end of your command line). You can also try the alternative syntax: --VolumePrefix=\some\test\path.

Volume prefixes should work under FUSE as they are used widely (e.g. by SSHFS-Win).