Extended attributes (EAs) are supported in OS/2's FAT file system and High Performance File System (HPFS). Extended attributes are not supported by the FAT file system used in versions of OS/2 prior to Version 1.2, nor are they supported in the DOS operating system.

EAs associated with a file object are not part of a file object or of its data, but are maintained separately and managed by the file system that manages that object. EAs reside on the volume on which the file object resides and are connected to their file object by pointers from the file object.

Therefore, EAs belonging to a file object are lost when moving that file object from a storage device managed by an OS/2 FAT or installable file system to a storage device managed by the old FAT file system.

EAs can be lost under other circumstances, as well:

• When a program that does not recognize EAs (for example, an editor written for DOS) performs a non-truncating open on the files with which the EAs are associated

• When the files they are associated with are sent over COM links

So that files with EAs can be manipulated under these circumstances, without losing their EAs, OS/2 provides a utility called EAUTIL EAUTIL enables users to separate extended attributes from the specified file object, optionally disassociating them from the file object. The extended attributes are placed into a specified HoldFile. This utility also enables users to reattach the separated extended attributes with their file objects.

EAUTIL can be applied to subdirectories, as well as to files. It does not support global file name characters in parameters; it operates on a single file object at each invocation.

Users can use EAUTIL to:

• Strip EAs off files to be edited with a program that does not recognize EAs.

• Place the EAs into normal files so they can be dealt with by old tools (such as backup, restore, and so on) or easily transmitted.

• Reattach EAs to files after the files have been brought back from the systems where EAs are not supported.