Gnu/coreutils/link-invocation

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12.1 link: Make a hard link via the link syscall

link creates a single hard link at a time. It is a minimalist interface to the system-provided link function. See Hard Links in The GNU C Library Reference Manual. It avoids the bells and whistles of the more commonly-used ln command (see ln invocation). Synopsis:

link filename linkname

filename must specify an existing file, and linkname must specify a nonexistent entry in an existing directory. link simply calls link (filename, linkname) to create the link.

On a GNU system, this command acts like ‘ln --directory --no-target-directory filename linkname’. However, the --directory and --no-target-directory options are not specified by POSIX, and the link command is more portable in practice.

If filename is a symbolic link, it is unspecified whether linkname will be a hard link to the symbolic link or to the target of the symbolic link. Use ln -P or ln -L to specify which behavior is desired.

An exit status of zero indicates success, and a nonzero value indicates failure.