NAME

undelete - attempt to recover a deleted file

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS



int undelete(const char *path)

DESCRIPTION

The undelete() function attempts to recover the deleted file named by path. Currently, this works only when the named object is a whiteout in a union filesystem. The system call removes the whiteout causing any objects in a lower layer of the union stack to become visible once more.

Eventually, the undelete functionality may be expanded to other filesystems able to recover deleted files such as the log-structured filesystem.

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:

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

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

[ENAMETOOLONG]
A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters.

[EEXIST]
The path does not reference a whiteout.

[ENOENT]
The named whiteout does not exist.

[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.

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

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

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

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

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

SEE ALSO

unlink(2), mount_union(8)

HISTORY

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