NAME    [Toc]    [Back]

     undelete - attempt to recover a deleted file

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     int
     undelete(const char *path);

DESCRIPTION    [Toc]    [Back]

     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    [Toc]    [Back]

     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    [Toc]    [Back]

     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    [Toc]    [Back]

     unlink(2), mount_union(8)

HISTORY    [Toc]    [Back]

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

BSD                            October 18, 1994                            BSD