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28 .\" @(#)link.2 8.3 (Berkeley) 1/12/94
37 .Nd make a hard file link
43 .Fn link "const char *name1" "const char *name2"
46 .Fa "int fd1" "const char *name1" "int fd2" "const char *name2" "int flag"
52 atomically creates the specified directory entry (hard link)
54 with the attributes of the underlying object pointed at by
56 If the link is successful: the link count of the underlying object
61 share equal access and rights
69 is not deleted and the link count of the
73 The object pointed at by the
76 must exist for the hard link to
82 must be in the same file system.
86 may not be a directory.
90 system call is equivalent to
92 except in the case where either
96 or both are relative paths.
97 In this case a relative path
99 is interpreted relative to
100 the directory associated with the file descriptor
102 instead of the current working directory and similarly for
104 and the file descriptor
109 are constructed by a bitwise-inclusive OR of flags from the following
112 .Bl -tag -width indent
113 .It Dv AT_SYMLINK_FOLLOW
116 names a symbolic link, a new link for the target of the symbolic link is
122 is passed the special value
128 parameter, the current working directory is used for the respective
137 the behavior is identical to a call to
142 .Dv AT_SYMLINK_FOLLOW
145 names a symbolic link, a new link is created for the symbolic link
154 will fail and no link will be created if:
157 A component of either path prefix is not a directory.
158 .It Bq Er ENAMETOOLONG
159 A component of either pathname exceeded 255 characters,
160 or entire length of either path name exceeded 1023 characters.
162 A component of either path prefix does not exist.
164 The file system containing the file named by
166 does not support links.
168 The link count of the file named by
172 A component of either path prefix denies search permission.
174 The requested link requires writing in a directory with a mode
175 that denies write permission.
177 Too many symbolic links were encountered in translating one of the pathnames.
193 has its immutable or append-only flag set, see the
195 manual page for more information.
197 The parent directory of the file named by
199 has its immutable flag set.
203 and the file named by
205 are on different file systems.
207 The directory in which the entry for the new link is being placed
208 cannot be extended because there is no space left on the file
209 system containing the directory.
211 The directory in which the entry for the new link
212 is being placed cannot be extended because the
213 user's quota of disk blocks on the file system
214 containing the directory has been exhausted.
216 An I/O error occurred while reading from or writing to
217 the file system to make the directory entry.
219 The requested link requires writing in a directory on a read-only file
222 One of the pathnames specified
223 is outside the process's allocated address space.
226 In addition to the errors returned by the
230 system call may fail if:
237 argument does not specify an absolute path and the
241 argument, respectively, is neither
243 nor a valid file descriptor open for searching.
247 argument is not valid.
253 argument is not an absolute path and
257 respectively, is neither
259 nor a file descriptor associated with a directory.
269 system call is expected to conform to
273 system call follows The Open Group Extended API Set 2 specification.
281 system call appeared in
286 system call traditionally allows the super-user to link directories which
287 corrupts the file system coherency.
288 This implementation no longer permits it.