xref: /freebsd/bin/ln/ln.1 (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
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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 BSD 4
41.Sh NAME
42.Nm ln ,
43.Nm link
44.Nd make links
45.Sh SYNOPSIS
46.Nm
47.Op Fl fisv
48.Ar source_file
49.Op target_file
50.Nm
51.Op Fl fisv
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 i
83Cause
84.Nm
85to write a prompt to standard error if the target file exists.
86If the response from the standard input begins with the character
87.Sq Li y
88or
89.Sq Li Y ,
90then unlink the target file so that the link may occur.
91Otherwise, do not attempt the link.
92(The
93.Fl i
94option overrides any previous
95.Fl f
96options.)
97.It Fl s
98Create a symbolic link.
99.It Fl v
100Cause
101.Nm
102to be verbose, showing files as they are processed.
103.El
104.Pp
105By default,
106.Nm
107makes
108.Em hard
109links.
110A hard link to a file is indistinguishable from the original directory entry;
111any changes to a file are effectively independent of the name used to reference
112the file.
113Hard links may not normally refer to directories and may not span file systems.
114.Pp
115A symbolic link contains the name of the file to
116which it is linked.  The referenced file is used when an
117.Xr open  2
118operation is performed on the link.
119A
120.Xr stat  2
121on a symbolic link will return the linked-to file; an
122.Xr lstat  2
123must be done to obtain information about the link.
124The
125.Xr readlink  2
126call may be used to read the contents of a symbolic link.
127Symbolic links may span file systems and may refer to directories.
128.Pp
129Given one or two arguments,
130.Nm
131creates a link to an existing file
132.Ar source_file  .
133If
134.Ar target_file
135is given, the link has that name;
136.Ar target_file
137may also be a directory in which to place the link;
138otherwise it is placed in the current directory.
139If only the directory is specified, the link will be made
140to the last component of
141.Ar source_file  .
142.Pp
143Given more than two arguments,
144.Nm
145makes links in
146.Ar target_dir
147to all the named source files.
148The links made will have the same name as the files being linked to.
149.Pp
150When the utility is called as
151.Nm link ,
152exactly two arguments must be supplied,
153neither of which may specify a directory.
154No options may be supplied in this simple mode of operation,
155which performs a
156.Xr link 2
157operation using the two passed arguments.
158.Sh SEE ALSO
159.Xr link 2 ,
160.Xr lstat 2 ,
161.Xr readlink 2 ,
162.Xr stat 2 ,
163.Xr symlink 2 ,
164.Xr symlink 7
165.Sh COMPATIBILITY
166The
167.Fl i
168and
169.Fl v
170options are non-standard and their use in scripts is not recommended.
171.Sh HISTORY
172An
173.Nm
174command appeared in
175.At v1 .
176The simplified
177.Nm link
178command conforms to
179.St -susv2 .
180