xref: /freebsd/bin/ln/ln.1 (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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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 s Op Fl F
45.Op Fl f | i
46.Op Fl hnv
47.Ar source_file
48.Op Ar target_file
49.Nm
50.Op Fl s Op Fl F
51.Op Fl f | i
52.Op Fl hnv
53.Ar source_file ...
54.Ar target_dir
55.Nm link
56.Ar source_file Ar target_file
57.Sh DESCRIPTION
58The
59.Nm
60utility creates a new directory entry (linked file) which has the
61same modes as the original file.
62It is useful for maintaining multiple copies of a file in many places
63at once without using up storage for the
64.Dq copies ;
65instead, a link
66.Dq points
67to the original copy.
68There are two types of links; hard links and symbolic links.
69How a link
70.Dq points
71to a file is one of the differences between a hard and symbolic link.
72.Pp
73The options are as follows:
74.Bl -tag -width flag
75.It Fl f
76If the target file already exists,
77then unlink it so that the link may occur.
78(The
79.Fl f
80option overrides any previous
81.Fl i
82options.)
83.It Fl F
84If the target file already exists and is a directory, then remove it
85so that the link may occur.
86The
87.Fl F
88option should be used with either
89.Fl f
90or
91.Fl i
92options.
93If none is specified,
94.Fl f
95is implied.
96The
97.Fl F
98option is a no-op unless
99.Fl s
100option is specified.
101.It Fl h
102If the
103.Ar target_file
104or
105.Ar target_dir
106is a symbolic link, do not follow it.
107This is most useful with the
108.Fl f
109option, to replace a symlink which may point to a directory.
110.It Fl i
111Cause
112.Nm
113to write a prompt to standard error if the target file exists.
114If the response from the standard input begins with the character
115.Sq Li y
116or
117.Sq Li Y ,
118then unlink the target file so that the link may occur.
119Otherwise, do not attempt the link.
120(The
121.Fl i
122option overrides any previous
123.Fl f
124options.)
125.It Fl n
126Same as
127.Fl h ,
128for compatibility with other
129.Nm
130implementations.
131.It Fl s
132Create a symbolic link.
133.It Fl v
134Cause
135.Nm
136to be verbose, showing files as they are processed.
137.El
138.Pp
139By default,
140.Nm
141makes
142.Em hard
143links.
144A hard link to a file is indistinguishable from the original directory entry;
145any changes to a file are effectively independent of the name used to reference
146the file.
147Hard links may not normally refer to directories and may not span file systems.
148.Pp
149A symbolic link contains the name of the file to
150which it is linked.
151The referenced file is used when an
152.Xr open 2
153operation is performed on the link.
154A
155.Xr stat 2
156on a symbolic link will return the linked-to file; an
157.Xr lstat 2
158must be done to obtain information about the link.
159The
160.Xr readlink 2
161call may be used to read the contents of a symbolic link.
162Symbolic links may span file systems and may refer to directories.
163.Pp
164Given one or two arguments,
165.Nm
166creates a link to an existing file
167.Ar source_file .
168If
169.Ar target_file
170is given, the link has that name;
171.Ar target_file
172may also be a directory in which to place the link;
173otherwise it is placed in the current directory.
174If only the directory is specified, the link will be made
175to the last component of
176.Ar source_file .
177.Pp
178Given more than two arguments,
179.Nm
180makes links in
181.Ar target_dir
182to all the named source files.
183The links made will have the same name as the files being linked to.
184.Pp
185When the utility is called as
186.Nm link ,
187exactly two arguments must be supplied,
188neither of which may specify a directory.
189No options may be supplied in this simple mode of operation,
190which performs a
191.Xr link 2
192operation using the two passed arguments.
193.Sh COMPATIBILITY
194The
195.Fl h ,
196.Fl i ,
197.Fl n
198and
199.Fl v
200options are non-standard and their use in scripts is not recommended.
201They are provided solely for compatibility with other
202.Nm
203implementations.
204.Pp
205The
206.Fl F
207option is
208.Fx
209extention and should not be used in portable scripts.
210.Sh SEE ALSO
211.Xr link 2 ,
212.Xr lstat 2 ,
213.Xr readlink 2 ,
214.Xr stat 2 ,
215.Xr symlink 2 ,
216.Xr symlink 7
217.Sh STANDARDS
218The
219.Nm
220utility conforms to
221.St -p1003.2-92 .
222.Pp
223The simplified
224.Nm link
225command conforms to
226.St -susv2 .
227.Sh HISTORY
228An
229.Nm
230command appeared in
231.At v1 .
232