RENAME(2)

NAME
rename - change the name or location of a file

SYNOPSIS
#include <stdio.h>

int rename(const char *oldpath, const char *newpath);

DESCRIPTION
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.

RETURN VALUE
On success, zero is returned. On error, -1 is returned, and errno is set appropriately.

ERRORS

EACCES
    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).)

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.)

EFAULT
    oldpath or newpath points outside your accessible address space.

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.

EISDIR
    newpath is an existing directory, but oldpath is not a directory.

ELOOP
    Too many symbolic links were encountered in resolving oldpath or newpath.

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.

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.

ENOSPC
    The device containing the file has no room for the new directory entry.

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.

ENOTEMPTY or EEXIST
    newpath is a non-empty directory, i.e., contains entries other than "." and "..".

EPERM or EACCES
    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.

EROFS
    The file is on a read-only filesystem.

EXDEV
    oldpath and newpath are not on the same mounted filesystem. (Linux permits a filesystem to be mounted at multiple points, but rename(2) does not work across different mount points, even if the same filesystem is mounted on both.)

CONFORMING TO
4.3BSD, C89, C99, POSIX.1-2001.

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.

SEE ALSO
mv(1), chmod(2), link(2), renameat(2), symlink(2), unlink(2), path_resolution(7)