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28 .\" @(#)unlink.2 8.1 (Berkeley) 6/4/93
31 .Dd September 23, 2020
38 .Nd remove directory entry
44 .Fn unlink "const char *path"
46 .Fn unlinkat "int dfd" "const char *path" "int flag"
48 .Fn funlinkat "int dfd" "const char *path" "int fd" "int flag"
53 removes the link named by
55 from its directory and decrements the link count of the
56 file which was referenced by the link.
57 If that decrement reduces the link count of the file
59 and no process has the file open, then
60 all resources associated with the file are reclaimed.
61 If one or more process have the file open when the last link is removed,
62 the link is removed, but the removal of the file is delayed until
63 all references to it have been closed.
67 may not be a directory.
71 system call is equivalent to
75 except in the case where
77 specifies a relative path.
78 In this case the directory entry to be removed is determined
79 relative to the directory associated with the file descriptor
81 instead of the current working directory.
85 are constructed by a bitwise-inclusive OR of flags from the following list,
88 .Bl -tag -width indent
90 Remove the directory entry specified by
94 as a directory, not a normal file.
96 Only unlink files and directories which are beneath of the topping
98 See the description of the
103 .It Dv AT_RESOLVE_BENEATH
104 Only walks paths below the topping directory.
105 See the description of the
106 .Dv O_RESOLVE_BENEATH
114 is passed the special value
118 parameter, the current working directory is used and the behavior is
119 identical to a call to
123 respectively, depending on whether or not the
129 system call can be used to unlink an already-opened file, unless that
130 file has been replaced since it was opened.
135 is already open as the file descriptor
137 Otherwise, the path will not be removed and an error will be returned.
154 A component of the path prefix is not a directory.
156 The named file is a directory.
157 .It Bq Er ENAMETOOLONG
158 A component of a pathname exceeded 255 characters,
159 or an entire path name exceeded 1023 characters.
161 The named file does not exist.
163 Search permission is denied for a component of the path prefix.
165 Write permission is denied on the directory containing the link
168 Too many symbolic links were encountered in translating the pathname.
170 The named file is a directory.
172 The named file has its immutable, undeletable or append-only flag set, see the
174 manual page for more information.
176 The parent directory of the named file has its immutable or append-only flag
179 The directory containing the file is marked sticky,
180 and neither the containing directory nor the file to be removed
181 are owned by the effective user ID.
183 An I/O error occurred while deleting the directory entry
184 or deallocating the inode.
186 Corrupted data was detected while reading from the file system.
188 The named file resides on a read-only file system.
193 points outside the process's allocated address space.
195 On file systems supporting copy-on-write or snapshots, there was not enough
196 free space to record metadata for the delete operation of the file.
199 In addition to the errors returned by the
208 argument does not specify an absolute path and the
212 nor a valid file descriptor open for searching.
220 argument names a directory that is not an empty directory,
221 or there are hard links to the directory other than dot or
222 a single entry in dot-dot.
230 does not name a directory.
234 argument is not valid.
238 argument is not an absolute path and
242 nor a file descriptor associated with a directory.
243 .It Bq Er ENOTCAPABLE
246 or contained a ".." component leading to a
247 directory outside of the directory hierarchy specified by
249 and the process is in capability mode.
250 .It Bq Er ENOTCAPABLE
257 does not have its tail fully contained under the topping directory,
263 In addition to the errors returned by
269 The file descriptor is not associated with the path.
280 system call follows The Open Group Extended API Set 2 specification.
288 system call appeared in
292 system call appeared in
297 system call traditionally allows the super-user to unlink directories which
298 can damage the file system integrity.
299 This implementation no longer permits it.