rename, renameat, renameat2 — change the name or location of a file
#include <stdio.h>
int
rename( |
const char *oldpath, |
const char *newpath); |
#include <fcntl.h> /* Definition of AT_* constants */ #include <stdio.h>
int
renameat( |
int olddirfd, |
| const char *oldpath, | |
| int newdirfd, | |
const char *newpath); |
int
renameat2( |
int olddirfd, |
| const char *oldpath, | |
| int newdirfd, | |
| const char *newpath, | |
unsigned int flags); |
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Note | |||||
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rename() renames a file,
moving it between directories if required. Any other hard
links to the file (as created using link(2)) are unaffected.
Open file descriptors for oldpath are also
unaffected.
If newpath already
exists, it will be atomically replaced (subject to a few
conditions; see ERRORS below), so that there is no point at
which another process attempting to access newpath will find it
missing.
If oldpath and
newpath are existing
hard links referring to the same file, then rename() does nothing, and returns a
success status.
If newpath exists
but the operation fails for some reason, rename() guarantees to leave an instance of
newpath in place.
oldpath can
specify a directory. In this case, newpath must either not exist,
or it must specify an empty directory.
However, when overwriting there will probably be a window
in which both oldpath
and newpath refer to
the file being renamed.
If oldpath refers
to a symbolic link, the link is renamed; if newpath refers to a symbolic
link, the link will be overwritten.
The renameat() system call
operates in exactly the same way as rename(), except for the differences
described here.
If the pathname given in oldpath is relative, then it
is interpreted relative to the directory referred to by the
file descriptor olddirfd (rather than
relative to the current working directory of the calling
process, as is done by rename() for a relative pathname).
If oldpath is
relative and olddirfd is the special value
AT_FDCWD, then oldpath is interpreted
relative to the current working directory of the calling
process (like rename()).
If oldpath is
absolute, then olddirfd is ignored.
The interpretation of newpath is as for oldpath, except that a
relative pathname is interpreted relative to the directory
referred to by the file descriptor newdirfd.
See openat(2) for an
explanation of the need for renameat().
renameat2() has an
additional flags
argument. A renameat2() call
with a zero flags
argument is equivalent to renameat().
The flags
argument is a bit mask consisting of zero or more of the
following flags:
RENAME_NOREPLACEDon't overwrite newpath. of the rename.
Return an error if newpath already
exists.
RENAME_EXCHANGEAtomically exchange oldpath and newpath. Both pathnames
must exist but may be of different types (e.g., one
could be a non-empty directory and the other a
symbolic link).
On success, zero is returned. On error, −1 is
returned, and errno is set
appropriately.
Write permission is denied for the directory
containing oldpath or newpath, or, search
permission is denied for one of the directories in the
path prefix of oldpath or newpath, or oldpath is a directory
and does not allow write permission (needed to update
the .. entry). (See also
path_resolution(7).)
The rename fails because oldpath or newpath is a directory
that is in use by some process (perhaps as current
working directory, or as root directory, or because it
was open for reading) or is in use by the system (for
example as mount point), while the system considers
this an error. (Note that there is no requirement to
return EBUSY in such
cases—there is nothing wrong with doing the
rename anyway—but it is allowed to return
EBUSY if the system
cannot otherwise handle such situations.)
The user's quota of disk blocks on the filesystem has been exhausted.
oldpath or
newpath points
outside your accessible address space.
The new pathname contained a path prefix of the old, or, more generally, an attempt was made to make a directory a subdirectory of itself.
newpath is
an existing directory, but oldpath is not a
directory.
Too many symbolic links were encountered in
resolving oldpath or newpath.
oldpath
already has the maximum number of links to it, or it
was a directory and the directory containing newpath has the maximum
number of links.
oldpath or
newpath was too
long.
The link named by oldpath does not exist;
or, a directory component in newpath does not exist;
or, oldpath or
newpath is an
empty string.
Insufficient kernel memory was available.
The device containing the file has no room for the new directory entry.
A component used as a directory in oldpath or newpath is not, in fact,
a directory. Or, oldpath is a directory,
and newpath
exists but is not a directory.
newpath is a
nonempty directory, that is, contains entries other
than "." and "..".
The directory containing oldpath has the sticky
bit (S_ISVTX) set and the
process's effective user ID is neither the user ID of
the file to be deleted nor that of the directory
containing it, and the process is not privileged
(Linux: does not have the CAP_FOWNER capability); or newpath is an existing
file and the directory containing it has the sticky bit
set and the process's effective user ID is neither the
user ID of the file to be replaced nor that of the
directory containing it, and the process is not
privileged (Linux: does not have the CAP_FOWNER capability); or the
filesystem containing pathname does not
support renaming of the type requested.
The file is on a read-only filesystem.
oldpath and
newpath are not
on the same mounted filesystem. (Linux permits a
filesystem to be mounted at multiple points, but
rename() does not work
across different mount points, even if the same
filesystem is mounted on both.)
The following additional errors can occur for renameat() and renameat2():
olddirfd or
newdirfd is not
a valid file descriptor.
oldpath is
relative and olddirfd is a file
descriptor referring to a file other than a directory;
or similar for newpath and newdirfd
The following additional errors can occur for renameat2():
flags
contains RENAME_NOREPLACE
and newpath
already exists.
An invalid flag was specified in flags, or both
RENAME_NOREPLACE and
RENAME_EXCHANGE were
specified.
The filesystem does not support one of the flags in
flags.
flags
contains RENAME_EXCHANGE
and newpath
does not exist.
renameat() was added to
Linux in kernel 2.6.16; library support was added to glibc in
version 2.4.
renameat2() was added to
Linux in kernel 3.15.
rename(): 4.3BSD, C89, C99,
POSIX.1-2001, POSIX.1-2008.
renameat():
POSIX.1-2008.
renameat2() is
Linux-specific.
On older kernels where renameat() is unavailable, the glibc
wrapper function falls back to the use of rename(). When oldpath and newpath are relative
pathnames, glibc constructs pathnames based on the symbolic
links in /proc/self/fd that
correspond to the olddirfd and newdirfd arguments.
On NFS filesystems, you can not assume that if the operation failed, the file was not renamed. If the server does the rename operation and then crashes, the retransmitted RPC which will be processed when the server is up again causes a failure. The application is expected to deal with this. See link(2) for a similar problem.
This page is part of release 3.72 of the Linux man-pages project. A
description of the project, information about reporting bugs,
and the latest version of this page, can be found at
http://www.kernel.org/doc/man−pages/.
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This manpage is Copyright (C) 1992 Drew Eckhardt; and Copyright (C) 1993 Michael Haardt; and Copyright (C) 1993,1995 Ian Jackson and Copyright (C) 2006, 2014 Michael Kerrisk %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. %%%LICENSE_END Modified Sat Jul 24 00:35:52 1993 by Rik Faith <faithcs.unc.edu> Modified Thu Jun 4 12:21:13 1998 by Andries Brouwer <aebcwi.nl> Modified Thu Mar 3 09:49:35 2005 by Michael Haardt <michaelmoria.de> 2007-03-25, mtk, added various text to DESCRIPTION. |