1.\" Copyright (c) 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Berkeley Software Design, Inc. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)revoke.2 8.1 (Berkeley) 6/4/93 32.\" $FreeBSD$ 33.\" 34.Dd January 25, 2016 35.Dt REVOKE 2 36.Os 37.Sh NAME 38.Nm revoke 39.Nd revoke file access 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In unistd.h 44.Ft int 45.Fn revoke "const char *path" 46.Sh DESCRIPTION 47The 48.Fn revoke 49system call invalidates all current open file descriptors in the system 50for the file named by 51.Fa path . 52Subsequent operations on any such descriptors 53fail, with the exceptions that a 54.Fn read 55from a character device file which has been revoked 56returns a count of zero (end of file), 57and a 58.Fn close 59system call will succeed. 60If the file is a special file for a device which is open, 61the device close function 62is called as if all open references to the file had been closed 63using a special close method which does not block. 64.Pp 65Access to a file may be revoked only by its owner or the super user. 66The 67.Fn revoke 68system call is currently supported only for block and character special 69device files. 70It is normally used to prepare a terminal device for a new login session, 71preventing any access by a previous user of the terminal. 72.Sh RETURN VALUES 73.Rv -std revoke 74.Sh ERRORS 75Access to the named file is revoked unless one of the following: 76.Bl -tag -width Er 77.It Bq Er ENOTDIR 78A component of the path prefix is not a directory. 79.It Bq Er ENAMETOOLONG 80A component of a pathname exceeded 255 characters, 81or an entire path name exceeded 1024 characters. 82.It Bq Er ENOENT 83The named file or a component of the path name does not exist. 84.It Bq Er EACCES 85Search permission is denied for a component of the path prefix. 86.It Bq Er ELOOP 87Too many symbolic links were encountered in translating the pathname. 88.It Bq Er EFAULT 89The 90.Fa path 91argument 92points outside the process's allocated address space. 93.It Bq Er EINVAL 94The implementation does not support the 95.Fn revoke 96operation on the named file. 97.It Bq Er EPERM 98The caller is neither the owner of the file nor the super user. 99.El 100.Sh SEE ALSO 101.Xr revoke 1 , 102.Xr close 2 103.Sh HISTORY 104The 105.Fn revoke 106system call first appeared in 107.Bx 4.3 Reno . 108.Sh BUGS 109The non-blocking close method is only correctly implemented for 110terminal devices. 111