172 lines
4.9 KiB
Groff
172 lines
4.9 KiB
Groff
.\" Copyright (c) 1980, 1991, 1993, 1994
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)chown.2 8.4 (Berkeley) 4/19/94
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd April 19, 1994
|
|
.Dt CHOWN 2
|
|
.Os BSD 4
|
|
.Sh NAME
|
|
.Nm chown ,
|
|
.Nm fchown ,
|
|
.Nm lchown
|
|
.Nd change owner and group of a file
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.Fd #include <unistd.h>
|
|
.Ft int
|
|
.Fn chown "const char *path" "uid_t owner" "gid_t group"
|
|
.Ft int
|
|
.Fn fchown "int fd" "uid_t owner" "gid_t group"
|
|
.Ft int
|
|
.Fn lchown "const char *path" "uid_t owner" "gid_t group"
|
|
.Sh DESCRIPTION
|
|
The owner ID and group ID of the file
|
|
named by
|
|
.Fa path
|
|
or referenced by
|
|
.Fa fd
|
|
is changed as specified by the arguments
|
|
.Fa owner
|
|
and
|
|
.Fa group .
|
|
The owner of a file may change the
|
|
.Fa group
|
|
to a group of which
|
|
he or she is a member,
|
|
but the change
|
|
.Fa owner
|
|
capability is restricted to the super-user.
|
|
.Pp
|
|
.Fn Chown
|
|
clears the set-user-id and set-group-id bits
|
|
on the file
|
|
to prevent accidental or mischievous creation of
|
|
set-user-id and set-group-id programs if not executed
|
|
by the super-user.
|
|
.Fn chown
|
|
follows symbolic links to operate on the target of the link
|
|
rather than the link itself.
|
|
.Pp
|
|
.Fn Fchown
|
|
is particularly useful when used in conjunction
|
|
with the file locking primitives (see
|
|
.Xr flock 2 ) .
|
|
.Pp
|
|
.Fn Lchown
|
|
is similar to
|
|
.Fn chown
|
|
but does not follow symbolic links.
|
|
.Pp
|
|
One of the owner or group id's
|
|
may be left unchanged by specifying it as -1.
|
|
.Sh RETURN VALUES
|
|
Zero is returned if the operation was successful;
|
|
-1 is returned if an error occurs, with a more specific
|
|
error code being placed in the global variable
|
|
.Va errno .
|
|
.Sh ERRORS
|
|
.Fn Chown
|
|
and
|
|
.Fn lchown
|
|
will fail and the file will be unchanged if:
|
|
.Bl -tag -width Er
|
|
.It Bq Er ENOTDIR
|
|
A component of the path prefix is not a directory.
|
|
.It Bq Er ENAMETOOLONG
|
|
A component of a pathname exceeded 255 characters,
|
|
or an entire path name exceeded 1023 characters.
|
|
.It Bq Er ENOENT
|
|
The named file does not exist.
|
|
.It Bq Er EACCES
|
|
Search permission is denied for a component of the path prefix.
|
|
.It Bq Er ELOOP
|
|
Too many symbolic links were encountered in translating the pathname.
|
|
.It Bq Er EPERM
|
|
The effective user ID is not the super-user.
|
|
.It Bq Er EROFS
|
|
The named file resides on a read-only file system.
|
|
.It Bq Er EFAULT
|
|
.Fa Path
|
|
points outside the process's allocated address space.
|
|
.It Bq Er EIO
|
|
An I/O error occurred while reading from or writing to the file system.
|
|
.El
|
|
.Pp
|
|
.Fn Fchown
|
|
will fail if:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EBADF
|
|
.Fa Fd
|
|
does not refer to a valid descriptor.
|
|
.It Bq Er EINVAL
|
|
.Fa Fd
|
|
refers to a socket, not a file.
|
|
.It Bq Er EPERM
|
|
The effective user ID is not the super-user.
|
|
.It Bq Er EROFS
|
|
The named file resides on a read-only file system.
|
|
.It Bq Er EIO
|
|
An I/O error occurred while reading from or writing to the file system.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr chgrp 1 ,
|
|
.Xr chmod 2 ,
|
|
.Xr flock 2 ,
|
|
.Xr chown 8
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn chown
|
|
function call is expected to conform to
|
|
.St -p1003.1-90 .
|
|
.Sh HISTORY
|
|
A
|
|
.Fn chown
|
|
function call appeared in
|
|
.At v7 .
|
|
The
|
|
.Fn fchown
|
|
function call
|
|
appeared in
|
|
.Bx 4.2 .
|
|
.Pp
|
|
The
|
|
.Fn chown
|
|
function was changed to follow symbolic links in
|
|
.Bx 4.4 .
|
|
The
|
|
.Fn lchown
|
|
function was added in
|
|
.Fx 3.0
|
|
to compensate for the loss of functionality.
|