xref: /freebsd/bin/ln/ln.1 (revision 4cf49a43559ed9fdad601bdcccd2c55963008675)
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35.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
36.\" $FreeBSD$
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 fsv
47.Ar source_file
48.Op target_file
49.Nm ln
50.Op Fl fsv
51.Ar source_file ...
52.Op target_dir
53.Sh DESCRIPTION
54The
55.Nm
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 and 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.It Fl v
76Cause
77.Nm
78to be verbose, showing files as they are processed.
79.El
80.Pp
81By default,
82.Nm
83makes
84.Em hard
85links.
86A hard link to a file is indistinguishable from the original directory entry;
87any changes to a file are effectively independent of the name used to reference
88the file.
89Hard links may not normally refer to directories and may not span file systems.
90.Pp
91A symbolic link contains the name of the file to
92which it is linked.  The referenced file is used when an
93.Xr open  2
94operation is performed on the link.
95A
96.Xr stat  2
97on a symbolic link will return the linked-to file; an
98.Xr lstat  2
99must be done to obtain information about the link.
100The
101.Xr readlink  2
102call may be used to read the contents of a symbolic link.
103Symbolic links may span file systems and may refer to directories.
104.Pp
105Given one or two arguments,
106.Nm
107creates a link to an existing file
108.Ar source_file  .
109If
110.Ar target_file
111is given, the link has that name;
112.Ar target_file
113may also be a directory in which to place the link;
114otherwise it is placed in the current directory.
115If only the directory is specified, the link will be made
116to the last component of
117.Ar source_file  .
118.Pp
119Given more than two arguments,
120.Nm
121makes links in
122.Ar target_dir
123to all the named source files.
124The links made will have the same name as the files being linked to.
125.Sh SEE ALSO
126.Xr link 2 ,
127.Xr lstat 2 ,
128.Xr readlink 2 ,
129.Xr stat 2 ,
130.Xr symlink 2 ,
131.Xr symlink 7
132.Sh COMPATIBILITY
133The
134.Fl v
135option is non-standard and its use in scripts is not recommended.
136.Sh HISTORY
137An
138.Nm
139command appeared in
140.At v1 .
141