xref: /netbsd-src/bin/ln/ln.1 (revision 63aea4bd5b445e491ff0389fe27ec78b3099dba3)
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33.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
34.\"
35.Dd October 29, 2007
36.Dt LN 1
37.Os
38.Sh NAME
39.Nm ln
40.Nd make links
41.Sh SYNOPSIS
42.Nm
43.Op Fl fhinsv
44.Ar source_file
45.Op Ar target_file
46.Nm
47.Op Fl fhinsv
48.Ar source_file ... target_dir
49.Sh DESCRIPTION
50The
51.Nm
52utility creates a new directory entry (linked file) which has the
53same modes as the original file.
54It is useful for maintaining multiple copies of a file in many places
55at once without using up storage for the
56.Dq copies ;
57instead, a link
58.Dq points
59to the original copy.
60There are two types of links: hard links and symbolic links.
61How a link
62.Dq points
63to a file is one of the differences between a hard or symbolic link.
64.Pp
65The options are as follows:
66.Bl -tag -width flag
67.It Fl f
68Unlink any already existing file, permitting the link to occur.
69.It Fl h
70If the
71.Ar target_file
72or
73.Ar target_dir
74is a symbolic link, do not follow it.
75This is most useful with the
76.Fl f
77option, to replace a symlink which may point to a directory.
78.It Fl i
79Cause
80.Nm
81to write a prompt to standard error if the target file exists.
82If the response from the standard input begins with the character
83.Sq Li y
84or
85.Sq Li Y ,
86then unlink the target file so that the link may occur.
87Otherwise, do not attempt the link.
88(The
89.Fl i
90option overrides any previous
91.Fl f
92options.)
93.It Fl n
94Same as
95.Fl h ,
96for compatibility with other
97.Nm
98implementations, namely GNU coreutils.
99.It Fl s
100Create a symbolic link.
101.It Fl v
102Cause
103.Nm
104to be verbose, showing files as they are processed.
105.El
106.Pp
107By default
108.Nm
109makes
110.Em hard
111links.
112A hard link to a file is indistinguishable from the original directory entry;
113any changes to a file are effective independent of the name used to reference
114the file.
115Hard links may not normally refer to directories and may not span file systems.
116.Pp
117A symbolic link contains the name of the file to
118which it is linked.
119The referenced file is used when an
120.Xr open 2
121operation is performed on the link.
122A
123.Xr stat 2
124on a symbolic link will return the linked-to file; an
125.Xr lstat 2
126must be done to obtain information about the link.
127The
128.Xr readlink 2
129call may be used to read the contents of a symbolic link.
130Symbolic links may span file systems and may refer to directories.
131.Pp
132Given one or two arguments,
133.Nm
134creates a link to an existing file
135.Ar source_file  .
136If
137.Ar target_file
138is given, the link has that name;
139.Ar target_file
140may also be a directory in which to place the link;
141otherwise it is placed in the current directory.
142If only the directory is specified, the link will be made
143to the last component of
144.Ar source_file  .
145.Pp
146Given more than two arguments,
147.Nm
148makes links in
149.Ar target_dir
150to all the named source files.
151The links made will have the same name as the files being linked to.
152.Sh SEE ALSO
153.Xr link 2 ,
154.Xr lstat 2 ,
155.Xr readlink 2 ,
156.Xr stat 2 ,
157.Xr symlink 2 ,
158.Xr symlink 7
159.Sh STANDARDS
160The
161.Nm
162utility conforms to
163.St -p1003.2-92 .
164.Pp
165The
166.Fl v
167option is an extension to
168.St -p1003.2-92 .
169.Sh HISTORY
170A
171.Nm
172utility appeared in
173.At v6 .
174