xref: /freebsd/bin/ln/ln.1 (revision 06064893b3c62c648518be78604fac29fc0d9d61)
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31.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
32.\" $FreeBSD$
33.\"
34.Dd December 30, 1993
35.Dt LN 1
36.Os
37.Sh NAME
38.Nm ln ,
39.Nm link
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 ...
49.Ar target_dir
50.Nm link
51.Ar source_file Ar target_file
52.Sh DESCRIPTION
53The
54.Nm
55utility creates a new directory entry (linked file) which has the
56same modes as the original file.
57It is useful for maintaining multiple copies of a file in many places
58at once without using up storage for the
59.Dq copies ;
60instead, a link
61.Dq points
62to the original copy.
63There are two types of links; hard links and symbolic links.
64How a link
65.Dq points
66to a file is one of the differences between a hard and symbolic link.
67.Pp
68The options are as follows:
69.Bl -tag -width flag
70.It Fl f
71If the target file already exists,
72then unlink it so that the link may occur.
73(The
74.Fl f
75option overrides any previous
76.Fl i
77options.)
78.It Fl h
79If the
80.Ar target_file
81or
82.Ar target_dir
83is a symbolic link, do not follow it.
84This is most useful with the
85.Fl f
86option, to replace a symlink which may point to a directory.
87.It Fl i
88Cause
89.Nm
90to write a prompt to standard error if the target file exists.
91If the response from the standard input begins with the character
92.Sq Li y
93or
94.Sq Li Y ,
95then unlink the target file so that the link may occur.
96Otherwise, do not attempt the link.
97(The
98.Fl i
99option overrides any previous
100.Fl f
101options.)
102.It Fl n
103Same as
104.Fl h ,
105for compatibility with other
106.Nm
107implementations.
108.It Fl s
109Create a symbolic link.
110.It Fl v
111Cause
112.Nm
113to be verbose, showing files as they are processed.
114.El
115.Pp
116By default,
117.Nm
118makes
119.Em hard
120links.
121A hard link to a file is indistinguishable from the original directory entry;
122any changes to a file are effectively independent of the name used to reference
123the file.
124Hard links may not normally refer to directories and may not span file systems.
125.Pp
126A symbolic link contains the name of the file to
127which it is linked.
128The referenced file is used when an
129.Xr open 2
130operation is performed on the link.
131A
132.Xr stat 2
133on a symbolic link will return the linked-to file; an
134.Xr lstat 2
135must be done to obtain information about the link.
136The
137.Xr readlink 2
138call may be used to read the contents of a symbolic link.
139Symbolic links may span file systems and may refer to directories.
140.Pp
141Given one or two arguments,
142.Nm
143creates a link to an existing file
144.Ar source_file .
145If
146.Ar target_file
147is given, the link has that name;
148.Ar target_file
149may also be a directory in which to place the link;
150otherwise it is placed in the current directory.
151If only the directory is specified, the link will be made
152to the last component of
153.Ar source_file .
154.Pp
155Given more than two arguments,
156.Nm
157makes links in
158.Ar target_dir
159to all the named source files.
160The links made will have the same name as the files being linked to.
161.Pp
162When the utility is called as
163.Nm link ,
164exactly two arguments must be supplied,
165neither of which may specify a directory.
166No options may be supplied in this simple mode of operation,
167which performs a
168.Xr link 2
169operation using the two passed arguments.
170.Sh SEE ALSO
171.Xr link 2 ,
172.Xr lstat 2 ,
173.Xr readlink 2 ,
174.Xr stat 2 ,
175.Xr symlink 2 ,
176.Xr symlink 7
177.Sh COMPATIBILITY
178The
179.Fl h ,
180.Fl i ,
181.Fl n
182and
183.Fl v
184options are non-standard and their use in scripts is not recommended.
185They are provided solely for compatibility with other
186.Nm
187implementations.
188.Sh STANDARDS
189The
190.Nm
191utility conforms to
192.St -p1003.2-92 .
193.Pp
194The simplified
195.Nm link
196command conforms to
197.St -susv2 .
198.Sh HISTORY
199An
200.Nm
201command appeared in
202.At v1 .
203