xref: /netbsd-src/bin/ln/ln.1 (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1.\"	$NetBSD: ln.1,v 1.14 1999/03/22 18:30:44 garbled Exp $
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37.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
38.\"
39.Dd December 30, 1993
40.Dt LN 1
41.Os
42.Sh NAME
43.Nm ln
44.Nd make links
45.Sh SYNOPSIS
46.Nm
47.Op Fl fhns
48.Ar source_file
49.Op target_file
50.Nm ""
51.Op Fl fhns
52.Ar source_file ...
53.Op target_dir
54.Sh DESCRIPTION
55The
56.Nm
57utility creates a new directory entry (linked file) which has the
58same modes as the original file.
59It is useful for maintaining multiple copies of a file in many places
60at once without using up storage for the
61.Dq copies ;
62instead, a link
63.Dq points
64to the original copy.
65There are two types of links; hard links and symbolic links.
66How a link
67.Dq points
68to a file is one of the differences between a hard or symbolic link.
69.Pp
70The options are as follows:
71.Bl -tag -width flag
72.It Fl f
73Unlink any already existing file, permitting the link to occur.
74.It Fl h
75If the
76.Ar target_file
77or
78.Ar target_dir
79is a symbolic link, do not follow it.  This is most useful with the
80.Fl f
81option, to replace a symlink which may point to a directory.
82.It Fl n
83Same as
84.Fl h ,
85for compatibility with other
86.Nm
87implementations.
88.It Fl s
89Create a symbolic link.
90.El
91.Pp
92By default
93.Nm
94makes
95.Em hard
96links.
97A hard link to a file is indistinguishable from the original directory entry;
98any changes to a file are effective independent of the name used to reference
99the file.
100Hard links may not normally refer to directories and may not span file systems.
101.Pp
102A symbolic link contains the name of the file to
103which it is linked.  The referenced file is used when an
104.Xr open  2
105operation is performed on the link.
106A
107.Xr stat  2
108on a symbolic link will return the linked-to file; an
109.Xr lstat  2
110must be done to obtain information about the link.
111The
112.Xr readlink  2
113call may be used to read the contents of a symbolic link.
114Symbolic links may span file systems and may refer to directories.
115.Pp
116Given one or two arguments,
117.Nm
118creates a link to an existing file
119.Ar source_file  .
120If
121.Ar target_file
122is given, the link has that name;
123.Ar target_file
124may also be a directory in which to place the link;
125otherwise it is placed in the current directory.
126If only the directory is specified, the link will be made
127to the last component of
128.Ar source_file  .
129.Pp
130Given more than two arguments,
131.Nm
132makes links in
133.Ar target_dir
134to all the named source files.
135The links made will have the same name as the files being linked to.
136.Sh SEE ALSO
137.Xr link 2 ,
138.Xr lstat 2 ,
139.Xr readlink 2 ,
140.Xr stat 2 ,
141.Xr symlink 2 ,
142.Xr symlink 7
143.Sh HISTORY
144A
145.Nm
146utility appeared in
147.At v6 .
148