rename renames a file, moving it between directories if required.
Any other hard links to the file (as created using
link(2) ) are 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
newpath exists but the operation fails for some reason
rename guarantees to leave an instance of
newpath in place.
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.
RETURN VALUE
On success, zero is returned. On error, -1 is returned, and
errno is set appropriately.
ERRORS
EISDIR
newpath is an existing directory, but
oldpath is not a directory.
EXDEV
oldpath " and " newpath are not on the same filesystem.
ENOTEMPTY " or " EEXIST
newpath is a non-empty directory, i.e., contains entries other than "." and "..".
EBUSY
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.)
EINVAL
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.
EMLINK
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.
ENOTDIR
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.
EFAULT
oldpath " or " newpath " points outside your accessible address space."
EACCES
Write access to the directory containing
oldpath " or " newpath is not allowed for the process's effective uid, or one of the
directories in
oldpath " or " newpath did not allow search (execute) permission, or
oldpath was a directory and did not allow write permission (needed to update
the
.. entry).
EPERM " or " EACCES
The directory containing
oldpath has the sticky bit set and the process's effective uid is neither that of root
nor the uid of the file to be deleted nor that of the directory containing it,
or
newpath is an existing file and the directory containing it has the sticky bit set
and the process's effective uid is neither that of root nor the uid of the
file to be replaced nor that of the directory containing it,
or the filesystem containing
pathname does not support renaming of the type requested.
ENAMETOOLONG
oldpath " or " newpath " was too long."
ENOENT
A directory component in
oldpath " or " newpath does not exist or is a dangling symbolic link.
ENOMEM
Insufficient kernel memory was available.
EROFS
The file is on a read-only filesystem.
ELOOP
Too many symbolic links were encountered in resolving
oldpath " or " newpath .
ENOSPC
The device containing the file has no room for the new directory
entry.
CONFORMING TO
POSIX, 4.3BSD, ANSI C
BUGS
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.
