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<title>Inode</title>

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<span id="openzim-page-title" class="mw-page-title-main">inode</span>

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<p>An <b>inode</b> (index node) is a <a href="Data_structure" title="Data structure">data structure</a> in a <a href="Unix_filesystem" title="Unix filesystem">Unix-style file system</a> that describes a <a href="File_system" title="File system">file-system</a> object such as a <a href="Computer_file" title="Computer file">file</a> or a <a href="Directory_(computing)" title="Directory (computing)">directory</a>. Each inode stores the attributes and disk block locations of the object's data.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> File-system object attributes may include <a href="Metadata" title="Metadata">metadata</a> (times of last change,<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> access, modification), as well as owner and <a href="File_system_permissions" class="mw-redirect" title="File system permissions">permission</a> data.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</p><p>A directory is a list of inodes with their assigned names. The list includes an entry for itself, its parent, and each of its children.

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<div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2></div><p>

There has been uncertainty on the <a href="Linux_kernel_mailing_list" title="Linux kernel mailing list">Linux kernel mailing list</a> about the reason for the "i" in "inode". In 2002, the question was brought to Unix pioneer <a href="Dennis_Ritchie" title="Dennis Ritchie">Dennis Ritchie</a>, who replied:<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> <style data-mw-deduplicate="TemplateStyles:r1244412712">

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</style></p><blockquote class="templatequote"><p>In truth, I don't know either. It was just a term that we started to use. "Index" is my best guess, because of the slightly unusual file system structure that stored the access information of files as a flat array on the disk, with all the hierarchical directory information living aside from this. Thus the i-number is an index in this array, the i-node is the selected element of the array. (The "i-" notation was used in the 1st edition manual; its hyphen was gradually dropped.)

</p></blockquote><p>

A 1978 paper by Ritchie and <a href="Ken_Thompson" title="Ken Thompson">Ken Thompson</a> bolsters the notion of "index" being the etymological origin of inodes. They wrote:<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><blockquote class="templatequote"><p>[…] a directory entry contains only a name for the associated file and a <a href="Pointer_(computer_programming)" title="Pointer (computer programming)">pointer</a> to the file itself. This pointer is an integer called the <i>i-number</i> (for index number) of the file. When the file is accessed, its i-number is used as an index into a system table (the <i>i-list</i>) stored in a known part of the device on which the directory resides. The entry found thereby (the file's <i>i-node</i>) contains the description of the file.

</p></blockquote><p> Additionally, Maurice J. Bach wrote that the word <i>inode</i> "is a contraction of the term index node and is commonly used in literature on the UNIX system".<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>

</p><div class="mw-heading mw-heading2"><h2 id="Details">Details</h2></div>

<p>A file system relies on data structures <i>about</i> the files, as opposed to the contents of that file. The former are called <i><a href="Metadata" title="Metadata">metadata</a></i>—data that describes data. Each file is associated with an <i>inode</i>, which is identified by an integer, often referred to as an <i>i-number</i> or <i>inode number</i>.

</p><p>Inodes store information about files and directories (folders), such as file ownership, access mode (read, write, execute permissions), and file type. The data may be called stat data, in reference to the <code><a href="Stat_(Unix)" class="mw-redirect" title="Stat (Unix)">stat</a></code> <a href="System_call" title="System call">system call</a> that provides the data to programs.

</p><p>The inode number indexes a table of inodes on the file system. From the inode number, the kernel's file system driver can access the inode contents, including the location of the file, thereby allowing access to the file. A file's inode number can be found using the <code>ls -i</code> command. The <code>ls -i</code> command prints the inode number in the first column of the report.

</p><p>On many older file systems, inodes are stored in one or more fixed-size areas that are set up at file system creation time, so the maximum number of inodes is fixed at file system creation, limiting the maximum number of files the file system can hold. A typical allocation heuristic for inodes in a file system is one inode for every 2K bytes contained in the filesystem.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>

</p><p>Some Unix-style file systems such as <a href="JFS_(file_system)" title="JFS (file system)">JFS</a>, <a href="XFS" title="XFS">XFS</a>, <a href="ZFS" title="ZFS">ZFS</a>, <a href="OpenZFS" title="OpenZFS">OpenZFS</a>, <a href="ReiserFS" title="ReiserFS">ReiserFS</a>, <a href="Btrfs" title="Btrfs">btrfs</a>, and <a href="APFS" class="mw-redirect" title="APFS">APFS</a> omit a fixed-size inode table, but must store equivalent data in order to provide equivalent capabilities. Common alternatives to the fixed-size table include <a href="B-tree" title="B-tree">B-trees</a> and the derived <a href="B%2B_tree" title="B+ tree">B+ trees</a>.

</p><p>File names and directory implications:

</p>

<ul><li>Inodes do not contain their <a href="Hard_link" title="Hard link">hard link</a> names, only other file metadata.</li>

<li>Unix directories are lists of association structures, each of which contains one filename and one inode number.</li>

<li>The file system driver must search a directory for a particular filename and then convert the filename to the correct corresponding inode number.</li></ul>

<p>The operating system kernel's in-memory representation of this data is called <code>struct inode</code> in <a href="Linux" title="Linux">Linux</a>. Systems derived from <a href="BSD" class="mw-redirect" title="BSD">BSD</a> use the term <code>vnode</code> (the "v" refers to the kernel's <a href="Virtual_file_system" title="Virtual file system">virtual file system</a> layer).

</p>

<div class="mw-heading mw-heading2"><h2 id="POSIX_inode_description">POSIX inode description</h2></div>

<p>The <a href="POSIX" title="POSIX">POSIX</a> standard mandates file-system behavior that is strongly influenced by traditional <a href="UNIX" class="mw-redirect" title="UNIX">UNIX</a> file systems. An inode is denoted by the phrase "file serial number", defined as a <i>per-file system</i> unique identifier for a file.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> That file serial number, together with the device ID of the device containing the file, uniquely identify the file within the whole system.<sup id="cite_ref-stat_10-0" class="reference"><a href="#cite_note-stat-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup>

</p><p>Within a POSIX system, a file has the following attributes<sup id="cite_ref-stat_10-1" class="reference"><a href="#cite_note-stat-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> which may be retrieved by the <code>stat</code> system call:

</p>

<ul><li>Device ID (this identifies the device containing the file; that is, the scope of uniqueness of the serial number).</li>

<li>File serial numbers.</li>

<li>The <a href="File_system_permissions" class="mw-redirect" title="File system permissions">file <i>mode</i></a>, which determines the file type and how the file's owner, users who are members of the file's group, and users who are neither the owner nor a member of the file's group can access the file.</li>

<li>A <a href="Reference_counting" title="Reference counting">link count</a> telling how many <a href="Hard_link" title="Hard link">hard links</a> point to the inode.</li>

<li>The <a href="User_identifier_(Unix)" class="mw-redirect" title="User identifier (Unix)">User ID</a> of the file's owner.</li>

<li>The <a href="Group_identifier_(Unix)" class="mw-redirect" title="Group identifier (Unix)">Group ID</a> of the file.</li>

<li>The device ID of the file if it is a <a href="Device_file" title="Device file">device file</a>.</li>

<li>The size of the file in <a href="Byte" title="Byte">bytes</a>.</li>

<li><a href="Timestamp" title="Timestamp">Timestamps</a> telling when the inode itself was last modified (<style data-mw-deduplicate="TemplateStyles:r886049734">

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</style><span class="monospaced">ctime</span>, <i>inode change time</i>), the file content last modified (<span class="monospaced">mtime</span>, <i>modification time</i>), and last accessed (<span class="monospaced">atime</span>, <i>access time</i>).</li>

<li>The preferred <a href="I/O" class="mw-redirect" title="I/O">I/O</a> block size.</li>

<li>The number of blocks allocated to this file.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Implications">Implications</h2></div>

<p>Filesystems designed with inodes will have the following administrative characteristics:

</p>

<div class="mw-heading mw-heading3"><h3 id="Multi-named_files_and_hard_links">Multi-named files and hard links</h3></div>

<p>Files can have multiple names. If multiple names hard link to the same inode then the names are equivalent; i.e., the first to be created has no special status. This is unlike <a href="Symbolic_link" title="Symbolic link">symbolic links</a>, which depend on the original name, not the inode (number).

</p>

<div class="mw-heading mw-heading3"><h3 id="inode_persistence_and_unlinked_files">inode persistence and unlinked files</h3></div>

<p>An inode may have no links. An inode without links represents a file with no remaining directory entries or paths leading to it in the filesystem. A file that has been deleted or lacks directory entries pointing to it is termed an 'unlinked' file.

</p><p>Such files are removed from the filesystem, freeing the occupied disk space for reuse. An inode without links remains in the filesystem until the resources (disk space and blocks) freed by the unlinked file are deallocated or the file system is modified.

</p><p>Although an unlinked file becomes invisible in the filesystem, its deletion is deferred until all processes with access to the file have finished using it, including executable files which are implicitly held open by the processes executing them.

</p>

<div class="mw-heading mw-heading3"><h3 id="inode_number_conversion_and_file_directory_path_retrieval">inode number conversion and file directory path retrieval</h3></div>

<p>It is typically not possible to map from an open file to the filename that was used to open it. When a program opens a file, the operating system converts the filename to an inode number and then discards the filename. As a result, functions like <a href="Direct.h" title="Direct.h"><span class="monospaced">getcwd()</span></a> and <a href="Direct.h" title="Direct.h"><span class="monospaced">getwd()</span></a> which retrieve the current <a href="Working_directory" title="Working directory">working directory</a> of the process, cannot directly access the filename.

</p><p>Beginning with the current directory, these functions search up to its <a href="Parent_directory" class="mw-redirect" title="Parent directory">parent directory</a>, then to the parent's parent, and so on, until reaching the <a href="Root_directory" title="Root directory">root directory</a>. At each level, the function looks for a directory entry whose inode matches that of the directory it just moved up from. Because the child directory's inode still exists as an entry in its <a href="Parent_directory" class="mw-redirect" title="Parent directory">parent directory</a>, it allows the function to reconstruct the <a href="Absolute_path" class="mw-redirect" title="Absolute path">absolute path</a> of the current <a href="Working_directory" title="Working directory">working directory</a>.

</p><p>Some operating systems maintain extra information to make this operation run faster. For example, in the <a href="Linux" title="Linux">Linux</a> VFS,<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> directory entry cache,<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> also known as dentry or dcache, are cache entries used by the <a href="Kernel_(operating_system)" title="Kernel (operating system)">kernel</a> to speed up filesystem operations by storing information about directory links in <a href="Random-access_memory" title="Random-access memory">RAM</a>.

</p>

<div class="mw-heading mw-heading3"><h3 id="Historical_possibility_of_directory_hard_linking">Historical possibility of directory hard linking</h3></div>

<p>Historically, it was possible to <a href="Hard_link" title="Hard link">hard link</a> directories. This made the directory structure an arbitrary <a href="Directed_graph" title="Directed graph">directed graph</a> contrary to a <a href="Directed_acyclic_graph" title="Directed acyclic graph">directed acyclic graph</a>. It was even possible for a directory to be its own parent. Modern systems generally prohibit this confusing state, except that the parent of <i>root</i> is still defined as root. The most notable exception to this prohibition is found in <a href="MacOS" title="MacOS">Mac OS X</a> (versions 10.5 and higher) which allows hard links of directories to be created on <a href="HFS%2B" class="mw-redirect" title="HFS+">HFS+</a> file systems by the superuser.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading3"><h3 id="inode_number_stability_and_non-Unix_file_systems">inode number stability and non-Unix file systems</h3></div>

<p>When a file is relocated to a different directory on the same file system, or when a disk <a href="Defragmentation" title="Defragmentation">defragmentation</a> alters its physical location, the file's inode number remains unchanged.

</p><p>This unique characteristic permits the file to be moved or renamed even during read or write operations, thereby ensuring continuous access without disruptions.

</p><p>This feature—having a file's metadata and <a href="Block_(data_storage)" title="Block (data storage)">data block</a> locations persist in a central <a href="Data_structure" title="Data structure">data structure</a>, irrespective of file renaming or moving—cannot be fully replicated in many <a href="List_of_file_systems" title="List of file systems">non-Unix file systems</a> like <a href="File_Allocation_Table" title="File Allocation Table">FAT</a> and its derivatives, as they lack a mechanism to maintain this invariant property when both the file's directory entry and its data are simultaneously relocated. In these file systems, moving or renaming a file might lead to more significant changes in the data structure representing the file, and the system does not keep a separate, central record of the file's <a href="Block_(data_storage)" title="Block (data storage)">data block</a> locations and <a href="Metadata" title="Metadata">metadata</a> as inodes do in <a href="Unix-like" title="Unix-like">Unix-like</a> systems.

</p>

<div class="mw-heading mw-heading3"><h3 id="Simplified_library_installation_with_inode_file_systems">Simplified library installation with inode file systems</h3></div>

<p>inode file systems allow a running process to continue accessing a library file even as another process is replacing that same file.

</p><p>This operation should be performed <a href="Atomicity_(programming)" class="mw-redirect" title="Atomicity (programming)">atomically</a>, meaning it should appear as a single operation that is either entirely completed or not done at all, with no intermediate state visible to other processes.

</p><p>During the <a href="Read%E2%80%93modify%E2%80%93write" title="Read–modify–write">replacement</a>, a new inode is created for the new <a href="Library_(computing)" title="Library (computing)">library file</a>, establishing an entirely new mapping. Subsequently, future access requests for that library will retrieve the newly installed version.

</p><p>When the operating system is replacing the file (and creating a new inode), it places a lock<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> on the inode<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> and possibly the containing directory.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> This prevents other processes from <a href="Readers%E2%80%93writer_lock" title="Readers–writer lock">reading or writing</a> to the file (inode)<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> during the update operation, thereby avoiding data inconsistency or corruption.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup>

</p><p>Once the update operation is complete, the lock is released. Any subsequent access to the file (via the inode) by any processes will now point to the new version of the library. Thus, making it possible to perform updates even when the library is in use by another process.

</p><p>One significant advantage of this mechanism is that it eliminates the need for a <a href="Booting" title="Booting">system reboot</a> to replace libraries currently in use. Consequently, systems can update or upgrade <a href="Software_libraries" class="mw-redirect" title="Software libraries">software libraries</a> seamlessly without interrupting running processes or operations.

</p>

<div class="mw-heading mw-heading3"><h3 id="Potential_for_inode_exhaustion_and_solutions">Potential for inode exhaustion and solutions</h3></div>

<p>When a file system is created, some file systems allocate a fixed number of inodes.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> This means that it is possible to run out of inodes on a file system, even if there is free space remaining in the file system. This situation often arises in use cases where there are many small files, such as on a server storing email messages, because each file, no matter how small, requires its own inode.

</p><p>Other file systems avoid this limitation by using dynamic inode allocation.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> Dynamic inode allocation allows a file system to create more inodes as needed instead of relying on a fixed number created at the time of file system creation.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> This can "grow" the file system by increasing the number of inodes available for new files and directories, thus avoiding the problem of running out of inodes.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Inlining">Inlining</h2></div>

<p>It can make sense to store very small files in the inode itself to save both space (no data block needed) and lookup time (no further disk access needed). This file system feature is called inlining. The strict separation of inode and file data thus can no longer be assumed when using modern file systems.

</p><p>If the data of a file fits in the space allocated for pointers to the data, this space can conveniently be used. For example, <a href="Ext2" title="Ext2">ext2</a> and its successors store the data of symlinks (typically file names) in this way if the data is no more than 60 bytes ("fast symbolic links").<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup>

</p><p><a href="Ext4" title="Ext4">Ext4</a> has a file system option called <code>inline_data</code> that allows ext4 to perform inlining if enabled during file system creation. Because an inode's size is limited, this only works for very small files.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="In_non-Unix_systems">In non-Unix systems</h2></div>

<ul><li><a href="NTFS" title="NTFS">NTFS</a> has a master file table (MFT) storing files in a B-tree. Each entry has a "fileID", analogous to the inode number, that uniquely refers to this entry.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> The three timestamps, a device ID, attributes, reference count, and file sizes are found in the entry, but unlike in POSIX the permissions are expressed through a different API.<sup id="cite_ref-win32stat_26-0" class="reference"><a href="#cite_note-win32stat-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> The on-disk layout is more complex.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> The earlier FAT file systems did not have such a table and were incapable of making hard links.

<ul><li>NTFS also has a concept of inlining small files into the MFT entry.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup></li>

<li>The derived <a href="ReFS" title="ReFS">ReFS</a> has a homologous MFT. ReFS has a 128-bit file ID; this extension was also backported to NTFS, which originally had a 64-bit file ID.<sup id="cite_ref-win32stat_26-1" class="reference"><a href="#cite_note-win32stat-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup></li></ul></li>

<li>The same stat-like <span class="monospaced">GetFileInformationByHandle</span> API can be used on <a href="Cluster_Shared_Volumes" title="Cluster Shared Volumes">Cluster Shared Volumes</a>, so it presumably has a similar concept of a file ID.<sup id="cite_ref-win32stat_26-2" class="reference"><a href="#cite_note-win32stat-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup></li></ul>

<ul><li><a href="Inode_pointer_structure" title="Inode pointer structure">inode pointer structure</a></li>

<li><a href="Inotify" title="Inotify">inotify</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><cite id="CITEREFBach1986" class="citation book cs1">Bach, Maurice J. (1986). <i>The Design of the UNIX Operating System</i>. Prentice Hall. p. 94. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1986duos.book.....B">1986duos.book.....B</a>.</cite></span>

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<li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_176">"Definitions - 3.176 File Serial Number"</a>. <i><a href="The_Open_Group" title="The Open Group">The Open Group</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">10 January</span> 2018</span>.</cite></span>

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<li id="cite_note-stat-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-stat_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-stat_10-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/stat.h.html">"<sys/stat.h>"</a>. <i><a href="The_Open_Group" title="The Open Group">The Open Group</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">15 January</span> 2018</span>.</cite></span>

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<li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><cite id="CITEREFGooch,_Richard" class="citation web cs1">Gooch, Richard. Enberg, Pekka (ed.). <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/vfs.html">"Overview of the Linux Virtual File System"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">20 May</span> 2023</span>.</cite></span>

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<li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><cite id="CITEREFRichard_Gooch" class="citation web cs1">Richard Gooch. Enberg, Pekka (ed.). <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/vfs.html#directory-entry-cache-dcache">"Directory Entry Cache (dcache)"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">20 May</span> 2023</span>.</cite></span>

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<li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://stackoverflow.com/questions/80875/what-is-the-unix-command-to-create-a-hardlink-to-a-directory-in-os-x">"What is the Unix command to create a hardlink to a directory in OS X?"</a>. <i><a href="Stack_Overflow" title="Stack Overflow">Stack Overflow</a></i>. 16 Jan 2011. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200105174407/https://stackoverflow.com/questions/80875/what-is-the-unix-command-to-create-a-hardlink-to-a-directory-in-os-x">Archived</a> from the original on 5 January 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">5 Jan</span> 2020</span>.</cite></span>

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<li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/locking.html">"Locking"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><cite id="CITEREFGooch,_Richard" class="citation web cs1">Gooch, Richard. Enberg, Pekka (ed.). <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/vfs.html#struct-inode-operations">"struct inode_operations"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/directory-locking.html">"Directory Locking"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/locking/locktypes.html">"Lock types and their rules"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><cite id="CITEREFvan_de_Ven,_A." class="citation web cs1">van de Ven, A., Molnar, I. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/locking/lockdep-design.html">"Runtime locking correctness validator"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite><span class="cs1-maint citation-comment"><code class="cs1-code">{{cite web}}</code>: CS1 maint: multiple names: authors list (link)</span></span>

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<li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/ext4/overview.html">"2. High Level Design"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/xfs-self-describing-metadata.html#inodes-and-dquots">"XFS Self Describing Metadata"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><cite id="CITEREFThe_kernel_development_community" class="citation web cs1">The kernel development community. <a rel="nofollow" class="external text" href="https://www.kernel.org/doc/html/latest/filesystems/ext4/overview.html#block-and-inode-allocation-policy">"2.7. Block and Inode Allocation Policy"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 May</span> 2023</span>.</cite></span>

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<li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><cite id="CITEREFVadala2002" class="citation book cs1">Vadala, Derek (2002). "6. Filesystems". <i>Managing RAID on Linux</i>. O'Reilly Media, Inc. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>9781565927308</bdi>.</cite></span>

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<li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.win.tue.nl/~aeb/linux/lk/lk-7.html">"The Linux kernel: Filesystems"</a>. <i>tue.nl</i>.</cite></span>

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<li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout#Inline_Data">"Ext4 Disk Layout"</a>. <i>kernel.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">August 18,</span> 2013</span>.</cite></span>

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<li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://stackoverflow.com/a/42475374">"Does Windows have Inode Numbers like Linux?"</a>. <i>Stack Overflow</i>.</cite></span>

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<li id="cite_note-win32stat-26"><span class="mw-cite-backlink">^ <a href="#cite_ref-win32stat_26-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-win32stat_26-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-win32stat_26-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfileinformationbyhandle">"GetFileInformationByHandle function (fileapi.h) - Win32 apps"</a>. <i>docs.microsoft.com</i>. 27 July 2022.</cite></span>

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<li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/a82e9105-2405-4e37-b2c3-28c773902d85">"[MS-FSCC]: NTFS Attribute Types"</a>. <i>docs.microsoft.com</i>. 20 September 2023.</cite></span>

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<li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://superuser.com/a/1185466">"Windows - Maximum size of file that can be stored entirely in NTFS Master File Table (MFT)"</a>.</cite></span>

</li>

</ol></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="https://developer.ibm.com/tutorials/l-linux-filesystem">Anatomy of the Linux File System</a></li>

<li><a rel="nofollow" class="external text" href="http://www.linfo.org/inode.html">Inode definition</a></li>

<li><a rel="nofollow" class="external text" href="http://linuxgazette.net/105/pitcher.html">Explanation of Inodes, Symlinks, and Hardlinks</a></li></ul>

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</style><div id="File_systems283" style="font-size:114%;margin:0 4em"><a href="File_system" title="File system">File systems</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div>

<ul><li><a href="Comparison_of_file_systems" title="Comparison of file systems">Comparison of file systems</a>

<ul><li><a href="Comparison_of_distributed_file_systems" title="Comparison of distributed file systems">distributed</a></li></ul></li>

<li><a href="Unix_filesystem" title="Unix filesystem">Unix filesystem</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Disk and<br>non-rotating</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="AdvFS" title="AdvFS">AdvFS</a></li>

<li><a href="Amiga_Fast_File_System" title="Amiga Fast File System">Amiga FFS</a></li>

<li><a href="Amiga_Old_File_System" title="Amiga Old File System">Amiga OFS</a></li>

<li><a href="AtheOS_File_System" class="mw-redirect" title="AtheOS File System">AthFS</a></li>

<li><a href="Bcachefs" title="Bcachefs">bcachefs</a></li>

<li>BFS

<ul><li><a href="Be_File_System" title="Be File System">Be File System</a></li>

<li><a href="Boot_File_System" title="Boot File System">Boot File System</a></li>

<li>Byte File System (<a href="Z/VM" title="Z/VM">z/VM</a>)</li></ul></li>

<li><a href="Btrfs" title="Btrfs">Btrfs</a></li>

<li>EFS

<ul><li><a href="Encrypting_File_System" title="Encrypting File System">Encrypting File System</a></li>

<li><a href="Extent_File_System" title="Extent File System">Extent File System</a></li></ul></li>

<li><a href="Episode_filesystem" title="Episode filesystem">Episode</a></li>

<ul><li><a href="ExFAT" title="ExFAT">exFAT</a></li></ul></li>

<li><a href="Files-11" title="Files-11">Files-11</a></li>

<li><a href="Fossil_(file_system)" title="Fossil (file system)">Fossil</a></li>

<li><a href="HAMMER_(file_system)" title="HAMMER (file system)">HAMMER</a>

<ul><li><a href="HAMMER2" title="HAMMER2">HAMMER2</a></li></ul></li>

<li><a href="Hierarchical_File_System_(Apple)" title="Hierarchical File System (Apple)">HFS</a> (<a href="Classic_Mac_OS" title="Classic Mac OS">Classic Mac OS</a>)</li>

<li>MFS

<ul><li><a href="Macintosh_File_System" title="Macintosh File System">Macintosh File System</a></li>

<li><a href="TiVo_Media_File_System" title="TiVo Media File System">TiVo Media File System</a></li></ul></li>

<li><a href="MINIX_file_system" title="MINIX file system">MINIX</a></li>

<li><a href="NetWare_File_System" title="NetWare File System">NetWare File System</a></li>

<li><a href="NILFS" title="NILFS">NILFS</a>

<ul><li><a href="NILFS" title="NILFS">NILFS2</a></li></ul></li>

<li><a href="OneFS_distributed_file_system" title="OneFS distributed file system">OneFS</a></li>

<li><a href="OpenZFS" title="OpenZFS">OpenZFS</a></li>

<li><a href="ReiserFS" title="ReiserFS">ReiserFS</a>

<ul><li><a href="Reiser4" title="Reiser4">Reiser4</a></li></ul></li>

<li><a href="Datalight#Reliance_family" title="Datalight">Reliance</a></li>

<li><a href="Datalight#Reliance_Nitro" title="Datalight">Reliance Nitro</a></li>

<li>SFS

<ul><li>Shared File System (<a href="VM_(operating_system)" title="VM (operating system)">VM</a>)</li>

<li><a href="Smart_File_System" title="Smart File System">Smart File System</a></li></ul></li>

<li><a href="Soup_(Apple)" title="Soup (Apple)">Soup (Apple)</a></li>

<li><a href="UBIFS" title="UBIFS">UBIFS</a></li>

<ul><li><a href="Soft_updates" title="Soft updates">soft updates</a></li>

<li><a href="Write_Ahead_Physical_Block_Logging" title="Write Ahead Physical Block Logging">WAPBL</a></li></ul></li>

<li><a href="Xiafs" title="Xiafs">Xiafs</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Optical_disc" title="Optical disc">Optical disc</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Flash_memory" title="Flash memory">Flash memory</a> and <a href="Solid-state_drive" title="Solid-state drive">SSD</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="ExFAT" title="ExFAT">exFAT</a></li>

<li><a href="EROFS" title="EROFS">EROFS</a></li>

</div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="host-side_wear_leveling27" scope="row" class="navbox-group" style="width:1%">host-side <a href="Wear_leveling" title="Wear leveling">wear leveling</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="LogFS" title="LogFS">LogFS</a></li>

<li><a href="NILFS" title="NILFS">NILFS</a>

<ul><li><a href="NILFS" title="NILFS">NILFS2</a></li></ul></li>

<li><a href="YAFFS" title="YAFFS">YAFFS</a></li>

<li><a href="UBIFS" title="UBIFS">UBIFS</a></li></ul>

</div></td></tr></tbody></table><div>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Clustered_file_system#Distributed_file_systems" title="Clustered file system">Distributed parallel</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="BeeGFS" title="BeeGFS">BeeGFS</a></li>

<li><a href="Google_File_System" title="Google File System">Google File System</a></li>

<li><a href="OrangeFS" title="OrangeFS">OrangeFS</a></li>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Network-attached_storage" title="Network-attached storage">NAS</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Andrew_File_System" title="Andrew File System">AFS</a> (<a href="OpenAFS" title="OpenAFS">OpenAFS</a>)</li>

<li><a href="Google_File_System" title="Google File System">Google File System</a></li>

<li><a href="Lustre_(file_system)" title="Lustre (file system)">Lustre</a></li>

<li><a href="Elliptics" title="Elliptics">POHMELFS</a></li>

<li><a href="Apache_Hadoop" title="Apache Hadoop">Hadoop</a></li>

<li><a href="SSHFS" title="SSHFS">SSHFS</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Specialized</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Boot_File_System" title="Boot File System">Boot File System</a></li>

<li><a href="Compact_Disc_File_System" title="Compact Disc File System">Compact Disc File System</a></li>

<li><a href="Cramfs" title="Cramfs">cramfs</a></li>

<li><a href="Davfs2" title="Davfs2">Davfs2</a></li>

<li><a href="EROFS" title="EROFS">EROFS</a></li>

<li><a href="FTPFS" title="FTPFS">FTPFS</a></li>

<li><a href="SquashFS" title="SquashFS">SquashFS</a></li>

<li><a href="FAT_filesystem_and_Linux" title="FAT filesystem and Linux">UMSDOS</a></li>

<li><a href="OverlayFS" title="OverlayFS">OverlayFS</a></li>

<li><a href="UnionFS" title="UnionFS">UnionFS</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Pseudo</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Configfs" title="Configfs">configfs</a></li>

<li><a href="Device_file" title="Device file">devfs</a></li>

<li><a href="Debugfs" title="Debugfs">debugfs</a></li>

<li><a href="Kernfs_(BSD)" title="Kernfs (BSD)">kernfs</a></li>

<li><a href="Procfs" title="Procfs">procfs</a></li>

<li>specfs</li>

<li><a href="Sysfs" title="Sysfs">sysfs</a></li>

<li><a href="Tmpfs" title="Tmpfs">tmpfs</a></li>

<li><a href="WinFS" title="WinFS">WinFS</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Filesystem-level_encryption" title="Filesystem-level encryption">Encrypted</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="ECryptfs" title="ECryptfs">eCryptfs</a></li>

<li><a href="EncFS" title="EncFS">EncFS</a></li>

<li><a href="Rubberhose_(file_system)" class="mw-redirect" title="Rubberhose (file system)">Rubberhose</a></li>

<li><a href="SSHFS" title="SSHFS">SSHFS</a></li>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Types</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Clustered_file_system" title="Clustered file system">Clustered</a>

<ul><li><a href="Global_file_system" title="Global file system">Global</a></li>

<li><a href="Self-certifying_File_System" title="Self-certifying File System">Self-certifying</a></li></ul></li>

<li><a href="Flash_file_system" title="Flash file system">Flash</a></li>

<li><a href="Journaling_file_system" title="Journaling file system">Journaling</a></li>

<li><a href="Log-structured_file_system" title="Log-structured file system">Log-structured</a></li>

<li><a href="Object_storage" title="Object storage">Object</a></li>

<li><a href="Record-oriented_filesystem" title="Record-oriented filesystem">Record-oriented</a></li>

<li><a href="Semantic_file_system" title="Semantic file system">Semantic</a></li>

<li><a href="Steganographic_file_system" title="Steganographic file system">Steganographic</a></li>

<li><a href="Synthetic_file_system" title="Synthetic file system">Synthetic</a></li>

<li><a href="Versioning_file_system" title="Versioning file system">Versioning</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Features</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Case_preservation" title="Case preservation">Case preservation</a></li>

<li><a href="Copy-on-write" title="Copy-on-write">Copy-on-write</a></li>

<li><a href="Data_deduplication" title="Data deduplication">Data deduplication</a></li>

<li><a href="Data_scrubbing" title="Data scrubbing">Data scrubbing</a></li>

<li><a href="Execute_in_place" title="Execute in place">Execute in place</a></li>

<li><a href="Extent_(file_systems)" title="Extent (file systems)">Extent</a></li>

<li><a href="File_attribute" title="File attribute">File attribute</a>

<ul><li><a href="Extended_file_attributes" title="Extended file attributes">Extended file attributes</a></li></ul></li>

<li><a href="File_change_log" title="File change log">File change log</a></li>

<li>Links

<li><a href="Symbolic_link" title="Symbolic link">Symbolic</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Computer_access_control" title="Computer access control">Access control</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Access-control_list" title="Access-control list">Access-control list</a></li>

<li><a href="Filesystem-level_encryption" title="Filesystem-level encryption">Filesystem-level encryption</a></li>

<li><a href="File-system_permissions" title="File-system permissions">Permissions</a>

<ul><li><a href="Chmod" title="Chmod">Modes</a></li>

<li><a href="Sticky_bit" title="Sticky bit">Sticky bit</a></li></ul></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Interface_(computing)" title="Interface (computing)">Interfaces</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="File_manager" title="File manager">File manager</a></li>

<li><a href="File_system_API" title="File system API">File system API</a>

<ul><li><a href="Installable_File_System" title="Installable File System">Installable File System</a></li></ul></li>

<li><a href="Virtual_file_system" title="Virtual file system">Virtual file system</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="List_of_file_systems" title="List of file systems">Lists</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="List_of_cryptographic_file_systems" title="List of cryptographic file systems">Cryptographic</a></li>

<li><a href="List_of_default_file_systems" title="List of default file systems">Default</a></li>

<li><a href="List_of_log-structured_file_systems" title="List of log-structured file systems">Log-structured</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Layouts</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Master_Boot_Record" class="mw-redirect" title="Master Boot Record">Master Boot Record</a></li>

<li><a href="GUID_Partition_Table" title="GUID Partition Table">GUID Partition Table</a></li>

<li><a href="Apple_Partition_Map" title="Apple Partition Map">Apple Partition Map</a></li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-06-26" href="https://en.wikipedia.org/wiki/?title=Inode&oldid=1297548023">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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