UNDELETE(2)

NAME
undelete - remove whiteout

LIBRARY
libc

SYNOPSIS
#include <unistd.h>
int
undelete(const char *path);

DESCRIPTION
Currently undelete works only when the named object is a whiteout in a union file system. The system call removes the whiteout causing any objects in a lower layer of the union stack to become visible once more.

RETURN VALUES
Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error.

ERRORS
The undelete() succeeds unless:

[EACCES]
    Search permission is denied for a component of the path prefix, or write permission is denied on the directory containing the name to be undeleted.

[EEXIST]
    The path does not reference a whiteout.

[EFAULT]
    path points outside the process's allocated address space.

[EINVAL]
    The pathname contains a character with the high-order bit set.

[EIO]
    An I/O error occurred while updating the directory entry.

[ELOOP]
    Too many symbolic links were encountered in translating the pathname.

[ENAMETOOLONG]
    A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters.

[ENOENT]
    The named whiteout does not exist.

[ENOTDIR]
    A component of the path prefix is not a directory.

[EPERM]
    The directory containing the name is marked sticky, and the containing directory is not owned by the effective user ID.

[EROFS]
    The name resides on a read-only file system.

SEE ALSO
unlink(2), mount_union(8)

HISTORY
An undelete function call first appeared in 4.4BSD -Lite.