xref: /freebsd/bin/ln/ln.1 (revision 7dfd9569a2f0637fb9a48157b1c1bfe5709faee3)
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32.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
33.\" $FreeBSD$
34.\"
35.Dd February 14, 2006
36.Dt LN 1
37.Os
38.Sh NAME
39.Nm ln ,
40.Nm link
41.Nd make links
42.Sh SYNOPSIS
43.Nm
44.Op Fl Ffhinsv
45.Ar source_file
46.Op Ar target_file
47.Nm
48.Op Fl Ffhinsv
49.Ar source_file ...
50.Ar target_dir
51.Nm link
52.Ar source_file Ar target_file
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
72If the target file already exists,
73then unlink it so that the link may occur.
74(The
75.Fl f
76option overrides any previous
77.Fl i
78options.)
79.It Fl F
80If the target file already exists and is a directory, then remove it
81so that the link may occur.
82The
83.Fl F
84option should be used with either
85.Fl f
86or
87.Fl i
88options.
89If none is specified,
90.Fl f
91is implied.
92The
93.Fl F
94option is a no-op unless
95.Fl s
96option is specified.
97.It Fl h
98If the
99.Ar target_file
100or
101.Ar target_dir
102is a symbolic link, do not follow it.
103This is most useful with the
104.Fl f
105option, to replace a symlink which may point to a directory.
106.It Fl i
107Cause
108.Nm
109to write a prompt to standard error if the target file exists.
110If the response from the standard input begins with the character
111.Sq Li y
112or
113.Sq Li Y ,
114then unlink the target file so that the link may occur.
115Otherwise, do not attempt the link.
116(The
117.Fl i
118option overrides any previous
119.Fl f
120options.)
121.It Fl n
122Same as
123.Fl h ,
124for compatibility with other
125.Nm
126implementations.
127.It Fl s
128Create a symbolic link.
129.It Fl v
130Cause
131.Nm
132to be verbose, showing files as they are processed.
133.El
134.Pp
135By default,
136.Nm
137makes
138.Em hard
139links.
140A hard link to a file is indistinguishable from the original directory entry;
141any changes to a file are effectively independent of the name used to reference
142the file.
143Hard links may not normally refer to directories and may not span file systems.
144.Pp
145A symbolic link contains the name of the file to
146which it is linked.
147The referenced file is used when an
148.Xr open 2
149operation is performed on the link.
150A
151.Xr stat 2
152on a symbolic link will return the linked-to file; an
153.Xr lstat 2
154must be done to obtain information about the link.
155The
156.Xr readlink 2
157call may be used to read the contents of a symbolic link.
158Symbolic links may span file systems and may refer to directories.
159.Pp
160Given one or two arguments,
161.Nm
162creates a link to an existing file
163.Ar source_file .
164If
165.Ar target_file
166is given, the link has that name;
167.Ar target_file
168may also be a directory in which to place the link;
169otherwise it is placed in the current directory.
170If only the directory is specified, the link will be made
171to the last component of
172.Ar source_file .
173.Pp
174Given more than two arguments,
175.Nm
176makes links in
177.Ar target_dir
178to all the named source files.
179The links made will have the same name as the files being linked to.
180.Pp
181When the utility is called as
182.Nm link ,
183exactly two arguments must be supplied,
184neither of which may specify a directory.
185No options may be supplied in this simple mode of operation,
186which performs a
187.Xr link 2
188operation using the two passed arguments.
189.Sh COMPATIBILITY
190The
191.Fl h ,
192.Fl i ,
193.Fl n
194and
195.Fl v
196options are non-standard and their use in scripts is not recommended.
197They are provided solely for compatibility with other
198.Nm
199implementations.
200.Pp
201The
202.Fl F
203option is
204.Fx
205extention and should not be used in portable scripts.
206.Sh SEE ALSO
207.Xr link 2 ,
208.Xr lstat 2 ,
209.Xr readlink 2 ,
210.Xr stat 2 ,
211.Xr symlink 2 ,
212.Xr symlink 7
213.Sh STANDARDS
214The
215.Nm
216utility conforms to
217.St -p1003.2-92 .
218.Pp
219The simplified
220.Nm link
221command conforms to
222.St -susv2 .
223.Sh HISTORY
224An
225.Nm
226command appeared in
227.At v1 .
228