Extended file attributes

<p>Extended file attributes are <a href="/facts/File_system/FdPm90uc">file system</a> features that enable users to associate <a href="/facts/Computer_file/FjFH3Ufm">computer files</a> with <a href="/facts/Metadata/qt35z79C">metadata</a> not interpreted by the filesystem, whereas regular attributes have a purpose strictly defined by the filesystem (such as <a href="/facts/File_system_permissions/DHq5SwI4">permissions</a> or records of creation and modification times). Unlike <a href="/facts/Fork_(file_system)/B1QFYk2t">forks</a>, which can usually be as large as the maximum file size, extended attributes are usually limited in size to a value significantly smaller than the maximum file size. Typical uses include storing the author of a document, the <a href="/facts/Character_encoding/ShJHIMoA">character encoding</a> of a plain-text document, or a <a href="/facts/Cyclic_redundancy_check/u2exo4sv">checksum</a>, <a href="/facts/Cryptographic_hash/cuxkgbST">cryptographic hash</a> or <a href="/facts/Digital_certificate/J7aYI4Bx">digital certificate</a>, and <a href="/facts/Discretionary_access_control/MTQRM7nr">discretionary access control</a> information.
</p><p>In <a href="/facts/Unix-like/YAKrAxzd">Unix-like</a> systems, extended attributes are usually abbreviated as xattr.
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Extended file attributes open-in-new

Extended file attributes