File permissions
This topic describes how file permissions are managed by the IBM Spectrum Archive.
LTFS manages write permissions for all users instead of having user- or group-based access control. File and directory ownership is not recorded to the tape medium. This means both that the file can have a read-only attribute for all users and a read-only attribute can be changed by any user.
LTFS-formatted media can be shared between Linux, OS X, and Windows. Linux and OS X manage file permissions using a 3-digit series (555 and 777). Table 1 shows how file permissions are mapped to a read-only attribute on Windows.
| File permissions on Linux and OS X | Read-only attribute on Windows |
|---|---|
| 555 | Read-only |
| 777 | Not read-only |
When a directory has a read-only attribute on a Linux system, a file on the directory cannot be created, deleted, or renamed.
On Linux and OS X, if the
ltfs command
specifies the -o umask option, write-protect permissions
are masked. On Windows, this
mask option is not supported. Note: LTFS Windows does not have user- or
group-based access control. The user can set or reset a read-only
attribute for a file by using the standard file properties window
or
attrib command. To do this from the standard file
properties window, the user right-clicks the file in Windows Explorer and then clicks the General tab.
The user can set or reset a read-only attribute for a directory only
by using the attrib command. To do this, the user
issues the attrib command with the R option
(for example, attrib +R abc.txt).