cygpath and unc paths

[Federico Kircheis]

On 09/12/2024 12.46, Corinna Vinschen via Cygwin wrote:
> On Dec  6 13:23, Federico Kircheis via Cygwin wrote:
>> Hello,
>>
>> was it considered to add a flag to cygpath to output a path in unc format?
> 
> No.  But it wouldn't be much work.

It would be very nice if it ever happens.

>> For example, the folder
>>
>> C:\test.
>>
>> cannot be accessed from many Windows applications (powershell and cmd
>> included) because of the trailing dot, while cygwin has no issue creating,
>> accessing and deleting such files/folders.
>>
>> Using an unc path
>>
>> \\?\C:\test.
>>
>> solves the issue for some programs, but cygpath currently misses an option
>> for creating such path.
> 
> As a workaround you can just prepend the long path prefix:
> 
>    echo -n '\\?\'; cygpath ...

Which is what I'm doing, plus special-casing

1)
root path, like C:\ , because for whatever reason \\?\C:\ is not valid, 
it has to be a subfolder (and trying to trick it with \\?\C:\\ does not 
work either).

2)
unmounted network drives (\\server\path)

I'm not sure how a --unc should handle those cases.
For all things I have in mind, not appending \\?\ is preferred, but 
someone might expect a hard error.

Either way, it is another reason why it makes sense for cygpath to 
handle those cases, currently I have to parse it's output before 
prepending '\\?\'.

>> Notice that creating a dos path leads to an error.
> 
> I don't understand. Creating which DOS path with which application?

I meant that it is not possible to create a DOS path to C:\test., thus 
using a dos path is not a viable workaround to unc:

----
 > cd 'C:/test.'
 > cygpath -ws .
cygpath: cannot create short name of .
----