Cygwin doesn't support IO_REPARSE_TAG_APPEXECLINK

Brian Inglis
Sat May 23 23:05:25 GMT 2020

On 2020-05-23 09:50, Marco Atzeri via Cygwin wrote:
> On 23.05.2020 17:09, Kagami Rosylight via Cygwin wrote:

>> I found that Cygwin can’t run UWP based CLI tools, as they expose their
>> executables as reparse points with the tag IO_REPARSE_TAG_APPEXECLINK which
>> Cygwin does not support.
>> Way to reproduce this issue on Cygwin:
>> 1. Install Python from Microsoft Store:
>> (assuming you don’t
>> already have python3.8 on your PATH.)
>> 2. Try running `python3.8` on Cygwin. It will say
>> “/cygdrive/c/Users/Kagami/AppData/Local/Microsoft/WindowsApps/python3.8:
>> Permission denied”
>> 3. Check it’s real path by `get-childitem -path
>> C:/Users/Kagami/AppData/Local/Microsoft/WindowsApps/python3.8.exe` on
>> PowerShell. It’s `C:\Program
>> Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.1008.0_x64__qbz5n2kfra8p0\python3.8.exe`.
>> 4. Try running python again with that path. This succeeds.
>> I posted this issue on MSYS2 GitHub repo
>> ( but I think Cygwin is
>> the right place to file this.
>> Relevant prior works:
>> * Python
>> * libuv
>> * PowerShell

> Not clear why you expect that a Windows specific tag as
> IO_REPARSE_TAG_APPEXECLINK should be supported on a Posix platform ?
> Moreover all the documentation from MS seems
> that seems a bit short to help third party in properly using it.

I think the general point being made is that /some/ Windows tools can not be run
from Cygwin.
I wonder what happens if the OP runs "cygstart python3.8"?

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

This email may be disturbing to some readers as it contains
too much technical detail. Reader discretion is advised.
[Data in IEC units and prefixes, physical quantities in SI.]

More information about the Cygwin mailing list