chown(S-osr5)
chown, lchown, fchown --
change owner and group of a file
Syntax
cc . . . -lc
#include <unistd.h>
#include <sys/stat.h>
int chown(const char *path, uid_t owner, gid_t group);
int lchown(const char *path, uid_t owner, gid_t group);
int fchown(int fildes, uid_t owner, gid_t group);
Description
The owner ID and group ID of the file specified
by path or referenced by the descriptor fildes,
are set to owner and group respectively. If
owner or group is specified as -1, the
corresponding ID of the file is not changed.
The function lchown sets the owner ID and group
ID of the named file just as chown does, except
in the case where the named file is a symbolic link. In this case
lchown changes the ownership of the symbolic link file
itself, while chown changes the ownership of the file or
directory to which the symbolic link refers.
If chown, lchown, or fchown is invoked
by other than root, the set-user-ID and
set-group-ID bits of the file mode, S_ISUID and
S_ISGID respectively, are cleared (see
chmod(S-osr5)).
When {_POSIX_CHOWN_RESTRICTED} is not in effect, the
effective user ID of the calling process must match the
owner of the file or the process must have the effective user
ID of root.
When {_POSIX_CHOWN_RESTRICTED} is in effect, the
chown, lchown, and fchown system calls
prevent the owner of the file from changing the owner ID
of the file and restrict the change of the group of the file to the
list of supplementary group IDs. This restriction does not
apply to processes having the effective user ID of
root.
{_POSIX_CHOWN_RESTRICTED} will be in effect if either the
user does not have the chown kernel authorization (as set
up by the system administrator in the Account Manager or the
usermod(ADM)
command) or if the kernel configurable CHOWN_RES is set.
Return values
On success, chown, fchown and lchown
return 0 and mark for update the st_ctime
field of the
file. On failure, chown, fchown and
lchown return -1, set errno to identify the
error, and the owner and group of the file are unchanged.
Diagnostics
In the following conditions, chown and lchown
fail and set errno to:
[EACCES]-
Search permission is denied on a component of the path prefix of
path.
[EACCES]-
Write permission on the named file is denied.
[EFAULT]-
path
points outside the allocated address space of the process.
[EINTR]-
A signal was caught during the chown or lchown
system calls.
[EINVAL]-
group or owner is out of range.
[EIO]-
An I/O error occurred while reading from or writing to the
filesystem.
[ELOOP]-
Too many symbolic links were encountered in translating
path.
[EMULTIHOP]-
Components of path require hopping to multiple remote
machines and file system type does not allow it. Too many symbolic
links were encountered in translating path.
[ENAMETOOLONG]-
The length of the path argument exceeds
{PATH_MAX}, or the length of a path component
exceeds {NAME_MAX} while {_POSIX_NO_TRUNC} is in
effect.
[ENOLINK]-
path points to a remote machine and the link to that
machine is no longer active.
[ENOTDIR]-
A component of the path prefix of path is not a directory.
[ENOENT]-
Either a component of the path prefix or the file referred to by
path does not exist or is a null pathname.
[EPERM]-
The effective user ID of the calling process does not
match the owner of the file and the calling process does not have
the appropriate privileges for changing file ownership.
[EROFS]-
The named file resides on a read-only file system.
In the following conditions, fchown fails and sets
errno to:
[EBADF]-
fildes is not an open file descriptor.
[EINVAL]-
group or owner is out of range.
[EPERM]-
The effective user ID of the calling process does not
match the owner of the file and the calling process does not have
the appropriate privilege.
[EROFS]-
The named file referred to by fildes resides on a
read-only file system.
[EINTR]-
A signal was caught during execution of the system call.
[EIO]-
An I/O error occurred while reading from or writing to the
file system.
[ENOLINK]-
fildes points to a remote machine and the link to that
machine is no longer active.
Files
/lib/libc.a-
linking library
See also
chgrp(C),
chmod(S-osr5),
chown(C)
Standards conformance
chown is conformant with:
AT&T SVID Issue 3;
X/Open Portability Guide, Issue 3, 1989
;
IEEE POSIX Std 1003.1-1990 System Application Program Interface (API) [C Language] (ISO/IEC 9945-1)
;
and
NIST FIPS 151-1
.
fchown and lchown are conformant with:
AT&T SVID Issue 3;
© 2005 The SCO Group, Inc. All rights reserved.
SCO OpenServer Release 6.0.0 -- 02 June 2005