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32 .\" @(#)ln.1 8.2 (Berkeley) 12/30/93
44 .Op Fl L | Fl P | Fl s Op Fl F
50 .Op Fl L | Fl P | Fl s Op Fl F
56 .Ar source_file Ar target_file
60 utility creates a new directory entry (linked file) for the file name
65 will be created with the same file modes as the
67 It is useful for maintaining multiple copies of a file in many places
68 at once without using up storage for the
73 There are two types of links; hard links and symbolic links.
76 to a file is one of the differences between a hard and symbolic link.
78 The options are as follows:
81 If the target file already exists and is a directory, then remove it
82 so that the link may occur.
85 option should be used with either
99 option is a no-op unless
103 When creating a hard link to a symbolic link,
104 create a hard link to the target of the symbolic link.
106 This option cancels the
110 When creating a hard link to a symbolic link,
111 create a hard link to the symbolic link itself.
112 This option cancels the
116 If the target file already exists,
117 then unlink it so that the link may occur.
120 option overrides any previous
130 is a symbolic link, do not follow it.
131 This is most useful with the
133 option, to replace a symlink which may point to a directory.
137 to write a prompt to standard error if the target file exists.
138 If the response from the standard input begins with the character
142 then unlink the target file so that the link may occur.
143 Otherwise, do not attempt the link.
146 option overrides any previous
152 for compatibility with other
156 Create a symbolic link.
160 to be verbose, showing files as they are processed.
162 Warn if the source of a symbolic link does not currently exist.
170 A hard link to a file is indistinguishable from the original directory entry;
171 any changes to a file are effectively independent of the name used to reference
173 Directories may not be hardlinked, and hard links may not span file systems.
175 A symbolic link contains the name of the file to
177 The referenced file is used when an
179 operation is performed on the link.
182 on a symbolic link will return the linked-to file; an
184 must be done to obtain information about the link.
187 call may be used to read the contents of a symbolic link.
188 Symbolic links may span file systems and may refer to directories.
190 Given one or two arguments,
192 creates a link to an existing file
196 is given, the link has that name;
198 may also be a directory in which to place the link;
199 otherwise it is placed in the current directory.
200 If only the directory is specified, the link will be made
201 to the last component of
204 Given more than two arguments,
208 to all the named source files.
209 The links made will have the same name as the files being linked to.
211 When the utility is called as
213 exactly two arguments must be supplied,
214 neither of which may specify a directory.
215 No options may be supplied in this simple mode of operation,
218 operation using the two passed arguments.
220 Create a symbolic link named
225 .Dl # ln -s /usr/src /home/src
228 .Pa /usr/local/bin/fooprog
230 .Pa /usr/local/bin/fooprog-1.0 :
232 .Dl # ln /usr/local/bin/fooprog-1.0 /usr/local/bin/fooprog
234 As an exercise, try the following commands:
235 .Bd -literal -offset indent
242 Note that both files have the same inode; that is,
244 is essentially an alias for the
247 This hard link exists so
249 may be invoked from shell scripts, for example, using the
253 In the next example, the second call to
257 and creates a replacement pointing to
259 .Bd -literal -offset indent
267 option, this would instead leave
276 This results from directory-walking.
278 An easy rule to remember is that the argument order for
282 The first argument needs to exist, the second one is created.
291 options are non-standard and their use in scripts is not recommended.
292 They are provided solely for compatibility with other
300 extension and should not be used in portable scripts.