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28 .\" @(#)chown.2 8.4 (Berkeley) 4/19/94
39 .Nd change owner and group of a file
45 .Fn chown "const char *path" "uid_t owner" "gid_t group"
47 .Fn fchown "int fd" "uid_t owner" "gid_t group"
49 .Fn lchown "const char *path" "uid_t owner" "gid_t group"
51 .Fn fchownat "int fd" "const char *path" "uid_t owner" "gid_t group" "int flag"
53 The owner ID and group ID of the file
58 is changed as specified by the arguments
62 The owner of a file may change the
65 he or she is a member,
68 capability is restricted to the super-user.
73 clears the set-user-id and set-group-id bits
75 to prevent accidental or mischievous creation of
76 set-user-id and set-group-id programs if not executed
81 follows symbolic links to operate on the target of the link
82 rather than the link itself.
87 is particularly useful when used in conjunction
88 with the file locking primitives (see
93 system call is similar to
95 but does not follow symbolic links.
99 system call is equivalent to the
103 except in the case where
105 specifies a relative path.
106 In this case the file to be changed is determined relative to the directory
107 associated with the file descriptor
109 instead of the current working directory.
113 are constructed by a bitwise-inclusive OR of flags from the following
116 .Bl -tag -width indent
117 .It Dv AT_SYMLINK_NOFOLLOW
120 names a symbolic link, ownership of the symbolic link is changed.
125 is passed the special value
129 parameter, the current working directory is used and the behavior is identical
134 respectively, depending on whether or not the
135 .Dv AT_SYMLINK_NOFOLLOW
140 One of the owner or group id's
141 may be left unchanged by specifying it as -1.
149 will fail and the file will be unchanged if:
152 A component of the path prefix is not a directory.
153 .It Bq Er ENAMETOOLONG
154 A component of a pathname exceeded 255 characters,
155 or an entire path name exceeded 1023 characters.
157 The named file does not exist.
159 Search permission is denied for a component of the path prefix.
161 Too many symbolic links were encountered in translating the pathname.
163 The operation would change the ownership, but the effective user ID is not the
166 The named file has its immutable or append-only flag set, see the
168 manual page for more information.
170 The named file resides on a read-only file system.
175 points outside the process's allocated address space.
177 An I/O error occurred while reading from or writing to the file system.
182 system call will fail if:
188 does not refer to a valid descriptor.
193 refers to a socket, not a file.
195 The effective user ID is not the super-user.
197 The named file resides on a read-only file system.
199 An I/O error occurred while reading from or writing to the file system.
202 In addition to the errors specified for
208 system call may fail if:
213 argument does not specify an absolute path and the
217 nor a valid file descriptor open for searching.
221 argument is not valid.
225 argument is not an absolute path and
229 nor a file descriptor associated with a directory.
240 system call is expected to conform to
244 system call follows The Open Group Extended API Set 2 specification.
252 system call appeared in
257 system call was changed to follow symbolic links in
261 system call was added in
263 to compensate for the loss of functionality.
267 system call appeared in