xref: /freebsd/bin/ln/ln.1 (revision b97fa2ef508bb1cc99621edb8b6d03845b55b8bd)
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35.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
36.\"	$Id$
37.\"
38.Dd December 30, 1993
39.Dt LN 1
40.Os BSD 4
41.Sh NAME
42.Nm ln
43.Nd make links
44.Sh SYNOPSIS
45.Nm ln
46.Op Fl fs
47.Ar source_file
48.Op target_file
49.Nm ln
50.Op Fl fs
51.Ar source_file ...
52.Op target_dir
53.Sh DESCRIPTION
54The
55.Nm ln
56utility creates a new directory entry (linked file) which has the
57same modes as the original file.
58It is useful for maintaining multiple copies of a file in many places
59at once without using up storage for the
60.Dq copies ;
61instead, a link
62.Dq points
63to the original copy.
64There are two types of links; hard links and symbolic links.
65How a link
66.Dq points
67to a file is one of the differences between a hard or symbolic link.
68.Pp
69The options are as follows:
70.Bl -tag -width flag
71.It Fl f
72Unlink any already existing file, permitting the link to occur.
73.It Fl s
74Create a symbolic link.
75.El
76.Pp
77By default
78.Nm ln
79makes
80.Em hard
81links.
82A hard link to a file is indistinguishable from the original directory entry;
83any changes to a file are effective independent of the name used to reference
84the file.
85Hard links may not normally refer to directories and may not span file systems.
86.Pp
87A symbolic link contains the name of the file to
88which it is linked.  The referenced file is used when an
89.Xr open  2
90operation is performed on the link.
91A
92.Xr stat  2
93on a symbolic link will return the linked-to file; an
94.Xr lstat  2
95must be done to obtain information about the link.
96The
97.Xr readlink  2
98call may be used to read the contents of a symbolic link.
99Symbolic links may span file systems and may refer to directories.
100.Pp
101Given one or two arguments,
102.Nm ln
103creates a link to an existing file
104.Ar source_file  .
105If
106.Ar target_file
107is given, the link has that name;
108.Ar target_file
109may also be a directory in which to place the link;
110otherwise it is placed in the current directory.
111If only the directory is specified, the link will be made
112to the last component of
113.Ar source_file  .
114.Pp
115Given more than two arguments,
116.Nm ln
117makes links in
118.Ar target_dir
119to all the named source files.
120The links made will have the same name as the files being linked to.
121.Sh SEE ALSO
122.Xr link 2 ,
123.Xr lstat 2 ,
124.Xr readlink 2 ,
125.Xr stat 2 ,
126.Xr symlink 2 ,
127.Xr symlink 7
128.Sh HISTORY
129A
130.Nm ln
131command appeared in
132.At v1 .
133