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52 lines
1.4 KiB
Markdown
52 lines
1.4 KiB
Markdown
# Hardlink
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Also the article for:
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- filename
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A hardlink associates a *filename* with a [file](/dict/terms/file). That
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name is an entry in a directory listing. Of course a file can have more
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hardlinks to it (usually the number of hardlinks to a file is limited),
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but all hardlinks to a file must reside on the same
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[filesystem](/dict/terms/filesystem) as the file itself!
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What you usually call a file is just a name for that file, and thus, a
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hardlink.
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The difference between a [symbolic link](/dict/terms/symlink) and a hard
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link is that there is no easy way to differentiate between a \'real\'
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file and a hard link, let\'s take a look at the example:
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\* create an empty file
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$ touch a
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\* create a hard link \'b\' and sym link \'c\' to empty file
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$ ln a b
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$ ln -s a c
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as you can see file(1) can\'t differentiate between a real file \'a\'
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and a hard link \'b\', but it can tell \'c\' is a sym link
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$ file *
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a: empty
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b: empty
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c: symbolic link to `a'
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`ls -i` prints out the inode numbers of files, if two files have the
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same inode number AND are on the same file system it means they are
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**hardlinked**.
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$ ls -i *
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5262 a 5262 b 5263 c
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hard links don\'t consume additional space on the filesystem, the space
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is freed when the last hard link pointing to it is deleted.
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## See also
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- [file](/dict/terms/file)
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- [filesystem](/dict/terms/filesystem)
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- [symlink](/dict/terms/symlink)
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