USD can't write layers when executable launched from beneath a Windows junction

[marktucker]

Description of Issue

Related to #1377, but with a somewhat different cause. When a USD executable is launched from within "D:/foo", where "D:/foo" is a symlink or junction to "F:/foo", and then tries to write to "D:/foo/bar.usda", it fails with a permission error (which isn't really a permission error).

Steps to Reproduce

1. Create a junction on Windows from D:/foo to F:/foo.
2. In a command prompt, navigate to D:/foo, and launch python.
3. Run the following:
   from pxr import Sdf
   l = Sdf.Layer.CreateAnonymous()
   l.Export("d:/foo/bar.usda")
4. The last line fails with 'Insufficient permissions to write to destination directory 'f:\foo\foo''

System Information (OS, Hardware)

Windows

Package Versions

USD 20.08 and 21.02

[jilliene]

Filed as internal issue #USD-6556

[sunyab]

Closing old issue, this was addressed by #1441.