xref: /freebsd/bin/ln/ln.1 (revision 7fcd5ae0d0ad1fdc89ecf839a7978c66322f8742)
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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 ln
47.Op Fl fisv
48.Ar source_file
49.Op target_file
50.Nm ln
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
75Unlink any already existing file, permitting the link to occur.
76The
77.Fl f
78option overrides any previous
79.Fl i
80options.
81.It Fl i
82Request confirmation before attempting to replace already existing file.
83The
84.Fl i
85option overrides any previous
86.Fl f
87options.
88.It Fl s
89Create a symbolic link.
90.It Fl v
91Cause
92.Nm
93to be verbose, showing files as they are processed.
94.El
95.Pp
96By default,
97.Nm
98makes
99.Em hard
100links.
101A hard link to a file is indistinguishable from the original directory entry;
102any changes to a file are effectively independent of the name used to reference
103the file.
104Hard links may not normally refer to directories and may not span file systems.
105.Pp
106A symbolic link contains the name of the file to
107which it is linked.  The referenced file is used when an
108.Xr open  2
109operation is performed on the link.
110A
111.Xr stat  2
112on a symbolic link will return the linked-to file; an
113.Xr lstat  2
114must be done to obtain information about the link.
115The
116.Xr readlink  2
117call may be used to read the contents of a symbolic link.
118Symbolic links may span file systems and may refer to directories.
119.Pp
120Given one or two arguments,
121.Nm
122creates a link to an existing file
123.Ar source_file  .
124If
125.Ar target_file
126is given, the link has that name;
127.Ar target_file
128may also be a directory in which to place the link;
129otherwise it is placed in the current directory.
130If only the directory is specified, the link will be made
131to the last component of
132.Ar source_file  .
133.Pp
134Given more than two arguments,
135.Nm
136makes links in
137.Ar target_dir
138to all the named source files.
139The links made will have the same name as the files being linked to.
140.Pp
141When the utility is called as
142.Nm link ,
143exactly two arguments must be supplied,
144neither of which may specify a directory.
145No options may be supplied in this simple mode of operation,
146which performs a
147.Xr link 2
148operation using the two passed arguments.
149.Sh SEE ALSO
150.Xr link 2 ,
151.Xr lstat 2 ,
152.Xr readlink 2 ,
153.Xr stat 2 ,
154.Xr symlink 2 ,
155.Xr symlink 7
156.Sh COMPATIBILITY
157The
158.Fl v
159and
160.Fl i
161options are non-standard and their use in scripts is not recommended.
162.Sh HISTORY
163An
164.Nm
165command appeared in
166.At v1 .
167The simplified
168.Nm link
169command conforms to
170.St -susv2 .
171