COPY fails to copy from \\wsl$

[samintz]

I cannot copy files from a WSL2 folder. I mapped drive W: to \\wsl$\Ubuntu-20.04. NET USE says it's a Plan 9 Network Provider.

$ copy * i:\.RaRecovery\
W:\git\Platform\Boot\ICE3\Utility\DebugJumper\ICE3_Eval\PostBuild_baremetal_lp64_el3_release\Firmware\PM.cms => I:\.RaRecovery\PM.cms
TCC: (Sys) The request was aborted.
W:\git\Platform\Boot\ICE3\Utility\DebugJumper\ICE3_Eval\PostBuild_baremetal_lp64_el3_release\Firmware\DebugJumper.cms => I:\.RaRecovery\DebugJumper.cms
TCC: (Sys) The request was aborted.
     0 files copied       2 failed

The copy succeeds from Explorer.
TCC 26.02.41 x64 Windows 10 [Version 10.0.19041.450]
TCC Build 41 Windows 10 Build 19041[/code]

 

[vefatica]

What's \\wsl$? I'm running WSL2 and I can't find any \\wsl$.

 

[samintz]

You can copy data from Windows into your WSL environment because your drives show up in /mnt/. For example, drive C: is /mnt/c.

Copying in the other direction can be done by copying from \\wsl$. From your bash prompt, you can type "explorer.exe ." and it will launch Explorer with the path to your current folder.

 

[samintz]

WSL1 uses files that are directly accessible from Windows - e.g. C:\Users\mintz\AppData\Local\lxss. But WSL2 files are inside of a VHDX file.
C:\Users\mintz\AppData\Local\Packages\CanonicalGroupLimited.Ubuntu20.04onWindows_79rhkp1fndgsc\LocalState\ext4.vhdx

 

[samintz]

You can tell which WSL you're running by running: wsl -l -v

$ wsl -l -v
  NAME                   STATE           VERSION
* Ubuntu-20.04           Running         2
  docker-desktop-data    Running         2
  Legacy                 Stopped         1
  Ubuntu                 Stopped         1
  docker-desktop         Running         2

 

[samintz]

And from your bash prompt: wslfetch

 

[vefatica]

I can do this (snipped) with TCC:

\\wsl$\ubuntu> dir

 Directory of  \\wsl$\ubuntu\*

2020-10-16  21:27         <DIR>    .
2020-10-16  21:27         <DIR>    ..
2019-07-04  00:51         <DIR>    bin
2019-05-21  10:42         <DIR>    boot
2020-10-16  21:27         <DIR>    dev

But I don't **SEE** WSL$\Ubuntu anywhere. l should I? And If I issue explorer.exe in bash (from any directory) explorer opens in my documents folder.

 

[rconn]

Does CMD work? The error you're getting is coming from Windows, not TCC.

 

[vefatica]

Here, this is cmd;

v:\> copy \\wsl$\ubuntu\home\vefatica\.bashrc
        1 file(s) copied.

And these are TCC.

\\wsl$\ubuntu\home\vefatica> copy .bashrc v:\
\\wsl$\ubuntu\home\vefatica\.bashrc => V:\.bashrc
TCC: (Sys) The request was aborted.
     0 files copied       1 failed

\\wsl$\ubuntu\home\vefatica> v:

v:\> copy \\wsl$\ubuntu\home\vefatica\.bashrc v:\
\\wsl$\ubuntu\home\vefatica\.bashrc => V:\.bashrc
TCC: (Sys) The request was aborted.
     0 files copied       1 failed

 

[samintz]

 

[vefatica]

Mine's a tad different but it is WSL2.

Windows 10 Linux Subsystem
vefatica@jj
BUILD: 18363
BRANCH: 19h1_release
RELEASE: Ubuntu 18.04.2 LTS
KERNEL: Linux 4.19.128-microsoft-standard
UPTIME: 0d 0h 3m

I can get here:

via a back door ... go there with TCC and do "explorer ." or (plugin) "shellex ." and also by typing the location in explorer's location bar. But I can't find a way to get there from "This PC" by pushing buttons.

I don't have WSL$ or Ubuntu in explorer's Network folder. Do you?

 

[Joe Caverly]

How about creating a shortcut?

I created this shortcut by dragging wsl$ up to the Desktop folder in explorer.

Joe

 

[vefatica]

I don't understand, Joe. Where was wsl$ in the first place so that it could be dragged anywhere?

 

[Joe Caverly]

From TCC;

e:\utils>cdd \\wsl$\ubuntu\home\jlc

\\wsl$\ubuntu\home\jlc>start .

Joe

 

[vefatica]

After those commands, I see this. But there's nothing **IN** Network. I never see anything in Network, even when my old computer is on (and networked).

 

[rconn]

File copies in TCC are done with the Windows API (CopyFileEx), so that's apparently either broken or deliberately doesn't support wsl copies. Only Microsoft knows for sure, and they didn't document it.

 

[vefatica]

File copies in TCC are done with the Windows API (CopyFileEx), so that's apparently either broken or deliberately doesn't support wsl copies. Only Microsoft knows for sure, and they didn't document it.

It works in this very simple form.

    BOOL bCancel;
    if ( CopyFileEx(L"\\\\wsl$\\ubuntu\\home\\vefatica\\.bashrc", L"v:\\.bashrc", NULL, 0, &bCancel, 0) == 0 )
        wprintf(L"LE = %lu\n", GetLastError());

That's in a project called "Sleep" and

d:\projects2019\sleep\x64\release> dir /k /m v:\.bashrc
TCC: (Sys) The system cannot find the file specified.
 "V:\.bashrc"

d:\projects2019\sleep\x64\release> Sleep.exe

d:\projects2019\sleep\x64\release> dir /k /m v:\.bashrc
2020-10-17  14:53           3,789  .bashrc

 

[vefatica]

That also works if I specify a do-nothing progress routine (return PROGRESS_CONTINUE).

 

[vefatica]

I'm getting really bizarre results. In a nutshell ...

1. This works.

BOOL bCancel;
CopyFileEx(L"\\\\wsl$\\ubuntu\\home\\vefatica\\.bashrc", L"v:\\.bashrc", NULL, NULL, &bCancel, 0);

2. This fails.

    WCHAR    szSrc[MAX_PATH]  = L"\\\\wsl$\\ubuntu\\home\\vefatica\\.bashrc",
            szDest[MAX_PATH] = L"v:\\.bashrc";
    BOOL bCancel;
    CopyFileEx(szSrc, szDest, NULL, NULL, &bCancel, 0)'

3. And (most bizarre) if both of the above appear in the source, both fail!

In all failing cases, GetLastError() is 1235 ("The request was aborted.").

Here's some source in case anyone wan't to play with it.

#include <Windows.h>
#include <stdio.h>

INT wmain(INT argc, WCHAR **argv)
{
    WCHAR    szSrc[MAX_PATH]  = L"\\\\wsl$\\ubuntu\\home\\vefatica\\.bashrc",
            szDest[MAX_PATH] = L"v:\\.bashrc";
    BOOL bCancel;

    if ( CopyFileEx(L"\\\\wsl$\\ubuntu\\home\\vefatica\\.bashrc", L"v:\\.bashrc", NULL, NULL, &bCancel, 0) == 0 )
        wprintf(L"1 - LE = %lu\n", GetLastError());

    //if ( CopyFileEx(szSrc, szDest, NULL, NULL, &bCancel, 0) == 0 )
    //    wprintf(L"2 - LE = %lu\n", GetLastError());

    return 0;
}

 

[vefatica]

Hmmm! My fault, I guess. If I set bCancel = FALSE before each call to CopyFileEx, everything works (makes sense, eh?).

This little test works fine with wsl$ paths.

#include <Windows.h>
#include <stdio.h>

INT wmain(INT argc, WCHAR **argv)
{
    if ( argc < 3 )
        return 1;
    BOOL bCancel;
    if ( !CopyFileEx(argv[1], argv[2], NULL, NULL, &(bCancel = FALSE), 0) )
        wprintf(L"LE = %lu\n", GetLastError());
    return 0;
}

 

[AnrDaemon]

Microsoft treating network names ending with $ as "system" names and won't show them in explorer.
F.e. you could create a network share named "mystuff$" and it will never appear in explorer, but will be visible in more honest programs (Far manager's Network browser plugin will show them as "hidden shares", for example).
"\\wsl$\" is another example of the same principle. This is a fake/special name for a local network service provided by the WSL2 host process, which exports all running VMs' root filesystems as network shares.