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.\" 33.Dd January 25, 2016 34.Dt REVOKE 2 35.Os 36.Sh NAME 37.Nm revoke 38.Nd revoke file access 39.Sh LIBRARY 40.Lb libc 41.Sh SYNOPSIS 42.In unistd.h 43.Ft int 44.Fn revoke "const char *path" 45.Sh DESCRIPTION 46The 47.Fn revoke 48system call invalidates all current open file descriptors in the system 49for the file named by 50.Fa path . 51Subsequent operations on any such descriptors 52fail, with the exceptions that a 53.Fn read 54from a character device file which has been revoked 55returns a count of zero (end of file), 56and a 57.Fn close 58system call will succeed. 59If the file is a special file for a device which is open, 60the device close function 61is called as if all open references to the file had been closed 62using a special close method which does not block. 63.Pp 64Access to a file may be revoked only by its owner or the super user. 65The 66.Fn revoke 67system call is currently supported only for block and character special 68device files. 69It is normally used to prepare a terminal device for a new login session, 70preventing any access by a previous user of the terminal. 71.Sh RETURN VALUES 72.Rv -std revoke 73.Sh ERRORS 74Access to the named file is revoked unless one of the following: 75.Bl -tag -width Er 76.It Bq Er ENOTDIR 77A component of the path prefix is not a directory. 78.It Bq Er ENAMETOOLONG 79A component of a pathname exceeded 255 characters, 80or an entire path name exceeded 1024 characters. 81.It Bq Er ENOENT 82The named file or a component of the path name does not exist. 83.It Bq Er EACCES 84Search permission is denied for a component of the path prefix. 85.It Bq Er ELOOP 86Too many symbolic links were encountered in translating the pathname. 87.It Bq Er EFAULT 88The 89.Fa path 90argument 91points outside the process's allocated address space. 92.It Bq Er EINVAL 93The implementation does not support the 94.Fn revoke 95operation on the named file. 96.It Bq Er EPERM 97The caller is neither the owner of the file nor the super user. 98.El 99.Sh SEE ALSO 100.Xr revoke 1 , 101.Xr close 2 102.Sh HISTORY 103The 104.Fn revoke 105system call first appeared in 106.Bx 4.3 Reno . 107.Sh BUGS 108The non-blocking close method is only correctly implemented for 109terminal devices. 110