1.\" Copyright (c) 1994 2.\" Jan-Simon Pendry 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. Neither the name of the University nor the names of its contributors 14.\" may be used to endorse or promote products derived from this software 15.\" without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.Dd March 30, 2020 30.Dt UNDELETE 2 31.Os 32.Sh NAME 33.Nm undelete 34.Nd attempt to recover a deleted file 35.Sh LIBRARY 36.Lb libc 37.Sh SYNOPSIS 38.In unistd.h 39.Ft int 40.Fn undelete "const char *path" 41.Sh DESCRIPTION 42The 43.Fn undelete 44system call attempts to recover the deleted file named by 45.Fa path . 46Currently, this works only when the named object 47is a whiteout in a union file system. 48The system call removes the whiteout causing 49any objects in a lower layer of the 50union stack to become visible once more. 51.Pp 52Eventually, the 53.Fn undelete 54functionality may be expanded to other file systems able to recover 55deleted files such as the log-structured file system. 56.Sh RETURN VALUES 57.Rv -std undelete 58.Sh ERRORS 59The 60.Fn undelete 61succeeds unless: 62.Bl -tag -width Er 63.It Bq Er ENOTDIR 64A component of the path prefix is not a directory. 65.It Bq Er ENAMETOOLONG 66A component of a pathname exceeded 255 characters, 67or an entire path name exceeded 1023 characters. 68.It Bq Er EEXIST 69The path does not reference a whiteout. 70.It Bq Er ENOENT 71The named whiteout does not exist. 72.It Bq Er EACCES 73Search permission is denied for a component of the path prefix. 74.It Bq Er EACCES 75Write permission is denied on the directory containing the name 76to be undeleted. 77.It Bq Er ELOOP 78Too many symbolic links were encountered in translating the pathname. 79.It Bq Er EPERM 80The directory containing the name is marked sticky, 81and the containing directory is not owned by the effective user ID. 82.It Bq Er EINVAL 83The last component of the path is 84.Ql .. . 85.It Bq Er EIO 86An I/O error occurred while updating the directory entry. 87.It Bq Er EINTEGRITY 88Corrupted data was detected while reading from the file system. 89.It Bq Er EROFS 90The name resides on a read-only file system. 91.It Bq Er EFAULT 92The 93.Fa path 94argument 95points outside the process's allocated address space. 96.El 97.Sh SEE ALSO 98.Xr unlink 2 , 99.Xr mount_unionfs 8 100.Sh HISTORY 101The 102.Fn undelete 103system call first appeared in 104.Bx 4.4 Lite . 105