Re: Cygwin tool to differ junctions from soft links?

[Brian Inglis <Brian.Inglis@Shaw.ca>]

On 2023-11-16 11:55, matthew patton via Cygwin wrote:
> On Thursday, November 16, 2023 at 03:50:24 AM EST, Andrey Repin wrote:
>>> Does Cygwin have a command line tool (Scriptable!) which can be used to
>>> differ between soft links and Windows junctions?

Distinguishing between types of Windows reparse points is not a POSIX or 
emulation function, so not of interest to Cygwin developers.

I thought about it when support was added, but then realized there was no nice 
place to add it within the platform, without going the non-portable Windows 
specific utility route, as in lsattr.

You could in a function or script by running lsattr -d which seems to fail on 
reparse points, then ls -dl which shows a Symbolic Link with a relative path, 
and a Junction with an absolute path, although it could just be a Symbolic Link 
with an absolute path.

Perhaps something like the following would be useful to Windows users who want 
to know this stuff:

	https://schinagl.priv.at/nt/hardlinkshellext/hardlinkshellext.html

>> It would be easier to help you, if you specify the purpose of your
>> request. I.e. what you want to achieve with such tool.
> AFAIK no. what I do is re-implement 'ln' with a wrapper because the Cygwin
> behavior (Junctions) was driving me up the wall.
> https://github.com/tb3088/shell-environment/blob/ccf7aa161899c2c4ebe2d9e980e674bc726a3ef3/.functions_os.CYGWIN_NT#L9

Cygwin never creates Windows Directory or Filesystem Junction reparse points, 
and by default it uses its own version of Unix path symlink files, preceded by a 
flag ("magic cookie") value, and with system attribute, to allow compatibility 
with FAT file system limitations, or else NFS symlinks on NFS filesystems.

CYGWIN env var settings allow creation of Windows shortcuts and symbolic link 
reparse points instead of its default (equivalent to winsymlinks:sys), when 
supported by the file system and Windows release:

	https://cygwin.com/cygwin-ug-net/using-cygwinenv.html

	https://cygwin.com/cygwin-ug-net/using.html#pathnames-symlinks

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

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry