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Universal Disk Format (OSTA-UDF/ECMA-167) filesystem support


driver ... udf udf_options ... &

Runs on:



Where driver is one of the devb-* drivers, and udf_options is one or more of the following, separated by commas:

The File Set number to mount; the default is 0.
The group ID to use for files with no specified group. The default is 0.
Specify what to do with "hidden" files. The hidden_mode can be one of:
The name of the filesystem metadata directory. The default is .info..
The user ID to use for files with no specified owner. The default is 0 (root).
How much of the UDF tag content (tag version, tag location, header checksum, and/or data CRC) to verify; one of the following:

Some UDF authoring utilities write incorrect tags, so it might be necessary to relax the verification if problems are observed. If you specify an option with a leading question mark (?), consults an internal blacklist of known bad utilities and automatically skip all checks; otherwise it operates at the level given after the question mark.

The Primary Volume number to mount; the default is 0.

In addition, you can specify any of the filesystem options described for


The shared object provides support for UDF (OSTA-UDF/ECMA-167) filesystems. It's automatically loaded by the devb-* drivers when mounting a UDF filesystem.

See also:

devb-*,,,,,,, mount, umount

"Universal Disk Format (UDF) filesystem" in the Working With Filesystems chapter of the User's Guide