Re: MSYS using Junctions quirk

On Mon, Aug 27, 2012 at 6:12 PM, dmccunney wrote:
> I'm not sure whether I'm encountering a bug or just getting bitten by
> lack of knowledge.
>

The latter is what I'm thinking.  BTW, support for MSYS happens on
mingw-user, the documentation needs changed.

>
> NTFS5 supports hard links for files and junctions for directories.  I
> use Hermann Schinagl's Link Shell Extension
> (http://schinagl.priv.at/nt/hardlinkshellext/hardlinkshellext.html)
> which provides context menu entries to create and manipulate such
> things.  Under Win2K/WinXP it does hard links out of the box.  Under
> Vista/Win7 it supports proper symbolic links, too.*
>
> I wanted a *nix like file system, so I used LSE to create a junction,
> and have Msys/1.0/bin appear as /bin.  That works fine.  I
> subsequently decided I'd prefer it to appear as /usr/bin, deleted the
> old junction, and created a new one.  That did *not* work fine.  The
> junction was created, /usr/bin shows in the file system and I can list
> the files in it, but attempting to actually execute any of them fails.
>  I can type the command at the prompt and I simply return to the
> prompt with the command not actually running.  If I create the
> junction as /bin, things work.  It appears Msys tools only work
> correctly through junctions created off of root, and fail if the
> junction is created off a sub-directory.  This seems to be Msys
> specific, as I have other sets on Win32 ports of *nix utilities, like
> the Gnuwin32 collection, that do work as expected.
>
> Right now, I have Msys mapped via a junction as /bin, and can live
> with it.  But I'm curious: *should* creating the junction as /usr/bin
> have worked, or am I running into an inherent limit in how Msys works,
> or have I found a bug?
>

Why?  When you start the MSYS shell it maps itself already to / and
/usr.  What are you trying to accomplish?

> * And too my surprise, a recent update to LSE pointed to an open
> source driver written by a Japanese developer that enables true
> symlinks in 2K and XP.  NTFS5 has the underlying infrastructure to
> support symlinks, but it's not exposed by the 2k/XP kernel.  The
> driver amends that oversite.

MSYS when I forked Cygwin to develop it did not have a Windows
junction or a Windows symlink to rely on and the way Cygwin had
emulated it did not work for a native application.  Therefore it was
removed and the functions return ENOSYS error.

-- 
Earnie
-- https://sites.google.com/site/earnieboyd

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