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.Dd January 25, 2016 32.Dt REVOKE 2 33.Os 34.Sh NAME 35.Nm revoke 36.Nd revoke file access 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In unistd.h 41.Ft int 42.Fn revoke "const char *path" 43.Sh DESCRIPTION 44The 45.Fn revoke 46system call invalidates all current open file descriptors in the system 47for the file named by 48.Fa path . 49Subsequent operations on any such descriptors 50fail, with the exceptions that a 51.Fn read 52from a character device file which has been revoked 53returns a count of zero (end of file), 54and a 55.Fn close 56system call will succeed. 57If the file is a special file for a device which is open, 58the device close function 59is called as if all open references to the file had been closed 60using a special close method which does not block. 61.Pp 62Access to a file may be revoked only by its owner or the super user. 63The 64.Fn revoke 65system call is currently supported only for block and character special 66device files. 67It is normally used to prepare a terminal device for a new login session, 68preventing any access by a previous user of the terminal. 69.Sh RETURN VALUES 70.Rv -std revoke 71.Sh ERRORS 72Access to the named file is revoked unless one of the following: 73.Bl -tag -width Er 74.It Bq Er ENOTDIR 75A component of the path prefix is not a directory. 76.It Bq Er ENAMETOOLONG 77A component of a pathname exceeded 255 characters, 78or an entire path name exceeded 1024 characters. 79.It Bq Er ENOENT 80The named file or a component of the path name does not exist. 81.It Bq Er EACCES 82Search permission is denied for a component of the path prefix. 83.It Bq Er ELOOP 84Too many symbolic links were encountered in translating the pathname. 85.It Bq Er EFAULT 86The 87.Fa path 88argument 89points outside the process's allocated address space. 90.It Bq Er EINVAL 91The implementation does not support the 92.Fn revoke 93operation on the named file. 94.It Bq Er EPERM 95The caller is neither the owner of the file nor the super user. 96.El 97.Sh SEE ALSO 98.Xr revoke 1 , 99.Xr close 2 100.Sh HISTORY 101The 102.Fn revoke 103system call first appeared in 104.Bx 4.3 Reno . 105.Sh BUGS 106The non-blocking close method is only correctly implemented for 107terminal devices. 108