RENAME(2)

NAME
rename - change the name or location of a file

SYNOPSIS
#include <unistd.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) are unaffected. If newpath already exists it will be atomically overwritten (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 or the system crashes 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
    newpath is a non-empty directory.

EBUSY
    newpath exists and is the current working directory or root directory of some process.

EEXIST
    The new pathname contained a path prefix of the old.

EINVAL
    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.

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
    The directory containing oldpath has the sticky bit set and the process's effective uid is neither the uid of the file to be deleted 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.

SEE ALSO
link(2), unlink(2), symlink(2), mv(1), link(8).