REVOKE(2)                 FreeBSD System Calls Manual                REVOKE(2)

NAME
     revoke - revoke file access

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     revoke(const char *path);

DESCRIPTION
     The revoke() system call invalidates all current open file descriptors in
     the system for the file named by path.  Subsequent operations on any such
     descriptors fail, with the exceptions that a read() from a character
     device file which has been revoked returns a count of zero (end of file),
     and a close() system call will succeed.  If the file is a special file
     for a device which is open, the device close function is called as if all
     open references to the file had been closed using a special close method
     which does not block.

     Access to a file may be revoked only by its owner or the super user.  The
     revoke() system call is currently supported only for block and character
     special device files.  It is normally used to prepare a terminal device
     for a new login session, preventing any access by a previous user of the
     terminal.

RETURN VALUES
     The revoke() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS
     Access to the named file is revoked unless one of the following:

     [ENOTDIR]          A component of the path prefix is not a directory.

     [ENAMETOOLONG]     A component of a pathname exceeded 255 characters, or
                        an entire path name exceeded 1024 characters.

     [ENOENT]           The named file or a component of the path name does
                        not exist.

     [EACCES]           Search permission is denied for a component of the
                        path prefix.

     [ELOOP]            Too many symbolic links were encountered in
                        translating the pathname.

     [EFAULT]           The path argument points outside the process's
                        allocated address space.

     [EINVAL]           The implementation does not support the revoke()
                        operation on the named file.

     [EPERM]            The caller is neither the owner of the file nor the
                        super user.

SEE ALSO
     revoke(1), close(2)

HISTORY
     The revoke() system call first appeared in 4.3BSD-Reno.

BUGS
     The non-blocking close method is only correctly implemented for terminal
     devices.

FreeBSD 13.1-RELEASE-p6        January 25, 2016        FreeBSD 13.1-RELEASE-p6