October 29, 2007 LN 1

### NAME

ln - make links

### SYNOPSIS

ln [-fhinsv] source_file [target_file] ln [-fhinsv] source_file ... target_dir

### DESCRIPTION

The ln utility creates a new directory entry (linked file) which has the same modes as the original file. It is useful for maintaining multiple copies of a file in many places at once without using up storage for the ``copies''; instead, a link ``points'' to the original copy. There are two types of links; hard links and symbolic links. How a link ``points'' to a file is one of the differences between a hard or symbolic link.

The options are as follows:

-f
  Unlink any already existing file, permitting the link to occur.

-h
  If the target_file or target_dir is a symbolic link, do not follow it. This is most useful with the -f option, to replace a symlink which may point to a directory.

-i
  Cause ln to write a prompt to standard error if the target file exists. If the response from the standard input begins with the character ````y`' or ````Y`', then unlink the target file so that the link may occur. Otherwise, do not attempt the link. (The -i option overrides any previous -f options.)

-n
  Same as -h, for compatibility with other ln implementations.

-s
  Create a symbolic link.

-v
  Cause ln to be verbose, showing files as they are processed.

By default ln makes hard links. A hard link to a file is indistinguishable from the original directory entry; any changes to a file are effective independent of the name used to reference the file. Hard links may not normally refer to directories and may not span file systems.

A symbolic link contains the name of the file to which it is linked. The referenced file is used when an open(2) operation is performed on the link. A stat(2) on a symbolic link will return the linked-to file; an lstat(2) must be done to obtain information about the link. The readlink(2) call may be used to read the contents of a symbolic link. Symbolic links may span file systems and may refer to directories.

Given one or two arguments, ln creates a link to an existing file source_file. If target_file is given, the link has that name; target_file may also be a directory in which to place the link; otherwise it is placed in the current directory. If only the directory is specified, the link will be made to the last component of source_file.

Given more than two arguments, ln makes links in target_dir to all the named source files. The links made will have the same name as the files being linked to.

### SEE ALSO

link(2), lstat(2), readlink(2), stat(2), symlink(2), symlink(7)

### STANDARDS

The ln utility conforms to IEEE Std 1003.2-1992 (``POSIX.2'') .

The -v option is an extension to IEEE Std 1003.2-1992 (``POSIX.2'') .

### HISTORY

A ln utility appeared in Version 6 `AT&T UNIX`.