/dev/null is a weird file

[jernejs]

That's precisely what stat says:

localhost ~ # stat /dev/null
  File: ‘/dev/null’
  Size: 0               Blocks: 0          IO Block: 512    weird file
Device: 0h/0d   Inode: 0           Links: 0
Access: (0000/?---------)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 1970-01-01 00:00:00.000000000 +0000
Modify: 1970-01-01 00:00:00.000000000 +0000
Change: 1970-01-01 00:00:00.000000000 +0000
 Birth: -

And it's causing problems with some programs (I don't remember what exactly was tripped by this in original userland, but I'm trying to run gentoo userland, and emerge fails sanity checks due to this).

Additionally, it appears there's no way to modify /dev - it always results in Operation not permitted.

[jpyper]

Maybe the whole idea behind the Linux/Ubuntu subsystem hasn't been fully implemented yet. The UNIX philosophy is that EVERYTHING is a file. For example, /dev/null is a virtual device file. This means that nothing, is something, and that something is represented in userland as a file.

On my Debian system, I get the following:

john@phobos:~$ stat /dev/null
File: '/dev/null'
Size: 0 Blocks: 0 IO Block: 4096 character special file
Device: 6h/6d Inode: 1037 Links: 1 Device type: 1,3
Access: (0666/crw-rw-rw-) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2016-04-06 20:33:12.884276144 -0700
Modify: 2016-04-06 20:33:12.884276144 -0700
Change: 2016-04-06 20:33:12.884276144 -0700
Birth: -

It looks like the Ubuntu subsystem doesn't see /dev/null as a "character special file" which I would think would redirect to >NUL on Windows.

[jernejs]

/dev/null should be a character device with major 1 and minor 3, but it isn't in lxss, so tests like this fail:

[ -c /dev/null ] || echo broken

[poizan42]

Shouldn't it be fine if /dev/null was simply a symlink to \Device\Null?

[thanosk]

One side-effect of this breaks sshd (openssh-server), as also mentioned here: MicrosoftDocs/WSL#17

[russalex]

The weird file is a known issue and something we intend to fix. It is currently on our backlog.

[mjgardner]

Another side-effect: I can't build a different version of Perl, either manually or using the perlbrew package, because its configure script checks for /dev/null's usability.

[ghost]

anybody want to take a guess at why this is in all of the binaries? https://gist.github.com/cloudkitsch/6f8bcb05f4006b5ea168eb6169ecbf12#file-gistfile1-txt-L335 quality control?