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Next: 4.7.2 Filter Functions Up: 4.7 Filters Previous: 4.7 Filters

4.7.1 Filter Examples

Here are a few examples of filters.

To compress data blocks of regular files:

To apply the Unix crypt(3)-based filter to all directories owned by user ``ezk'' (uid 2301) on the first file system:

To expand shell environment variables that may be embedded in names of symbolic links:

One may want to ignore errors returned by a caching file system, since data not in the cache can always be retrieved from the source. For example, if a file could not be written because the cache is full, that should not result in the vnode operation failing. To ignore out-of-space errors from the cache file system, one might use the ``ignore'' (null) filter:

To log all attempts to read my directories by any non-system user other than the owner:

Erez Zadok