NTFS permission not flowing to the newly created files and subfolder

Consider the present scenario. A NFS share has been created on a C drive. Desired NTFS permission are given to the share. On the folder properties- security-advance the option below is checked

Then the registry key “KeepInheritance” is set to 1.
HKEY_LOCAL_MACHINE\Software\Microsoft\Server for NFS\CurrentVersion\Mapping
Go to the Edit menu, click REG_DWORD, type 1, and then click OK.

With these setting the expected behavior is the NTFS permission will flow to the entire file/sub folder inside the NFS share.

But, we recently got a scenario where it was not happening. After troubleshooting we found that whenever the file/folder was created from Korn/C shell, the NTFS permission was not getting inherited.

The registry key “keepinheritance” is specifically used by the UNIX clients.

Korn shell and C shell are Interix shells and Interix does not honor NTFS inheritance settings. This is why whenever the files were created on the share from Korn/C shell the permission was not getting inherited. For Interix, any DACLs it creates will not contain any inheritance ACEs nor will it honor the inheritance ACEs that may be present on the parent directory.