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41 .Op Fl L | Fl P | Fl s Op Fl F
47 .Op Fl L | Fl P | Fl s Op Fl F
53 .Ar source_file Ar target_file
57 utility creates a new directory entry (linked file) for the file name
62 will be created with the same file modes as the
64 It is useful for maintaining multiple copies of a file in many places
65 at once without using up storage for the
70 There are two types of links; hard links and symbolic links.
73 to a file is one of the differences between a hard and symbolic link.
75 The options are as follows:
78 If the target file already exists and is a directory, then remove it
79 so that the link may occur.
82 option should be used with either
96 option is a no-op unless
100 When creating a hard link to a symbolic link,
101 create a hard link to the target of the symbolic link.
103 This option cancels the
107 When creating a hard link to a symbolic link,
108 create a hard link to the symbolic link itself.
109 This option cancels the
113 If the target file already exists,
114 then unlink it so that the link may occur.
117 option overrides any previous
127 is a symbolic link, do not follow it.
128 This is most useful with the
130 option, to replace a symlink which may point to a directory.
134 to write a prompt to standard error if the target file exists.
135 If the response from the standard input begins with the character
139 then unlink the target file so that the link may occur.
140 Otherwise, do not attempt the link.
143 option overrides any previous
149 for compatibility with other
153 Create a symbolic link.
157 to be verbose, showing files as they are processed.
159 Warn if the source of a symbolic link does not currently exist.
167 A hard link to a file is indistinguishable from the original directory entry;
168 any changes to a file are effectively independent of the name used to reference
170 Directories may not be hardlinked, and hard links may not span file systems.
172 A symbolic link contains the name of the file to
174 The referenced file is used when an
176 operation is performed on the link.
179 on a symbolic link will return the linked-to file; an
181 must be done to obtain information about the link.
184 call may be used to read the contents of a symbolic link.
185 Symbolic links may span file systems and may refer to directories.
187 Given one or two arguments,
189 creates a link to an existing file
193 is given, the link has that name;
195 may also be a directory in which to place the link;
196 otherwise it is placed in the current directory.
197 If only the directory is specified, the link will be made
198 to the last component of
201 Given more than two arguments,
205 to all the named source files.
206 The links made will have the same name as the files being linked to.
208 When the utility is called as
210 exactly two arguments must be supplied,
211 neither of which may specify a directory.
212 No options may be supplied in this simple mode of operation,
215 operation using the two passed arguments.
217 Create a symbolic link named
222 .Dl # ln -s /usr/src /home/src
225 .Pa /usr/local/bin/fooprog
227 .Pa /usr/local/bin/fooprog-1.0 :
229 .Dl # ln /usr/local/bin/fooprog-1.0 /usr/local/bin/fooprog
231 As an exercise, try the following commands:
232 .Bd -literal -offset indent
239 Note that both files have the same inode; that is,
241 is essentially an alias for the
244 This hard link exists so
246 may be invoked from shell scripts, for example, using the
250 In the next example, the second call to
254 and creates a replacement pointing to
256 .Bd -literal -offset indent
264 option, this would instead leave
273 This results from directory-walking.
275 An easy rule to remember is that the argument order for
279 The first argument needs to exist, the second one is created.
288 options are non-standard and their use in scripts is not recommended.
289 They are provided solely for compatibility with other
297 extension and should not be used in portable scripts.