xref: /freebsd/bin/ln/ln.1 (revision caa2db3be99609f52d3d2ce00e2442349742f3f0)
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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
41.Sh NAME
42.Nm ln ,
43.Nm link
44.Nd make links
45.Sh SYNOPSIS
46.Nm
47.Op Fl fhinsv
48.Ar source_file
49.Op target_file
50.Nm
51.Op Fl fhinsv
52.Ar source_file ...
53.Op target_dir
54.Nm link
55.Ar source_file Ar target_file
56.Sh DESCRIPTION
57The
58.Nm
59utility creates a new directory entry (linked file) which has the
60same modes as the original file.
61It is useful for maintaining multiple copies of a file in many places
62at once without using up storage for the
63.Dq copies ;
64instead, a link
65.Dq points
66to the original copy.
67There are two types of links; hard links and symbolic links.
68How a link
69.Dq points
70to a file is one of the differences between a hard and symbolic link.
71.Pp
72The options are as follows:
73.Bl -tag -width flag
74.It Fl f
75If the target file already exists,
76then unlink it so that the link may occur.
77(The
78.Fl f
79option overrides any previous
80.Fl i
81options.)
82.It Fl h
83If the
84.Ar target_file
85or
86.Ar target_dir
87is a symbolic link, do not follow it.  This is most useful with the
88.Fl f
89option, to replace a symlink which may point to a directory.
90.It Fl i
91Cause
92.Nm
93to write a prompt to standard error if the target file exists.
94If the response from the standard input begins with the character
95.Sq Li y
96or
97.Sq Li Y ,
98then unlink the target file so that the link may occur.
99Otherwise, do not attempt the link.
100(The
101.Fl i
102option overrides any previous
103.Fl f
104options.)
105.It Fl n
106Same as
107.Fl h ,
108for compatibility with other
109.Nm
110implementations.
111.It Fl s
112Create a symbolic link.
113.It Fl v
114Cause
115.Nm
116to be verbose, showing files as they are processed.
117.El
118.Pp
119By default,
120.Nm
121makes
122.Em hard
123links.
124A hard link to a file is indistinguishable from the original directory entry;
125any changes to a file are effectively independent of the name used to reference
126the file.
127Hard links may not normally refer to directories and may not span file systems.
128.Pp
129A symbolic link contains the name of the file to
130which it is linked.  The referenced file is used when an
131.Xr open  2
132operation is performed on the link.
133A
134.Xr stat  2
135on a symbolic link will return the linked-to file; an
136.Xr lstat  2
137must be done to obtain information about the link.
138The
139.Xr readlink  2
140call may be used to read the contents of a symbolic link.
141Symbolic links may span file systems and may refer to directories.
142.Pp
143Given one or two arguments,
144.Nm
145creates a link to an existing file
146.Ar source_file  .
147If
148.Ar target_file
149is given, the link has that name;
150.Ar target_file
151may also be a directory in which to place the link;
152otherwise it is placed in the current directory.
153If only the directory is specified, the link will be made
154to the last component of
155.Ar source_file  .
156.Pp
157Given more than two arguments,
158.Nm
159makes links in
160.Ar target_dir
161to all the named source files.
162The links made will have the same name as the files being linked to.
163.Pp
164When the utility is called as
165.Nm link ,
166exactly two arguments must be supplied,
167neither of which may specify a directory.
168No options may be supplied in this simple mode of operation,
169which performs a
170.Xr link 2
171operation using the two passed arguments.
172.Sh SEE ALSO
173.Xr link 2 ,
174.Xr lstat 2 ,
175.Xr readlink 2 ,
176.Xr stat 2 ,
177.Xr symlink 2 ,
178.Xr symlink 7
179.Sh COMPATIBILITY
180The
181.Fl h ,
182.Fl i ,
183.Fl n
184and
185.Fl v
186options are non-standard and their use in scripts is not recommended.
187They are provided solely for compatibility with other
188.Nm
189implementations.
190.Sh STANDARDS
191The
192.Nm
193utility conforms to
194.St -p1003.2-92 .
195.Pp
196The simplified
197.Nm link
198command conforms to
199.St -susv2 .
200.Sh HISTORY
201An
202.Nm
203command appeared in
204.At v1 .
205