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+.\"
+.\" Copyright (c) 2012 The FreeBSD Foundation
+.\" All rights reserved.
+.\"
+.\" This documentation was written by Pawel Jakub Dawidek under sponsorship
+.\" the FreeBSD Foundation.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd March 27, 2014
+.Dt CAP_FCNTLS_LIMIT 2
+.Os
+.Sh NAME
+.Nm cap_fcntls_limit ,
+.Nm cap_fcntls_get
+.Nd manage allowed fcntl commands
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In sys/capsicum.h
+.Ft int
+.Fn cap_fcntls_limit "int fd" "uint32_t fcntlrights"
+.Ft int
+.Fn cap_fcntls_get "int fd" "uint32_t *fcntlrightsp"
+.Sh DESCRIPTION
+If a file descriptor is granted the
+.Dv CAP_FCNTL
+capability right, the list of allowed
+.Xr fcntl 2
+commands can be selectively reduced (but never expanded) with the
+.Fn cap_fcntls_limit
+system call.
+.Pp
+A bitmask of allowed fcntls commands for a given file descriptor can be obtained
+with the
+.Fn cap_fcntls_get
+system call.
+.Sh FLAGS
+The following flags may be specified in the
+.Fa fcntlrights
+argument or returned in the
+.Fa fcntlrightsp
+argument:
+.Bl -tag -width CAP_FCNTL_GETOWN
+.It Dv CAP_FCNTL_GETFL
+Permit
+.Dv F_GETFL
+command.
+.It Dv CAP_FCNTL_SETFL
+Permit
+.Dv F_SETFL
+command.
+.It Dv CAP_FCNTL_GETOWN
+Permit
+.Dv F_GETOWN
+command.
+.It Dv CAP_FCNTL_SETOWN
+Permit
+.Dv F_SETOWN
+command.
+.El
+.Sh RETURN VALUES
+.Rv -std
+.Sh ERRORS
+.Fn cap_fcntls_limit
+succeeds unless:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The
+.Fa fd
+argument is not a valid descriptor.
+.It Bq Er EINVAL
+An invalid flag has been passed in
+.Fa fcntlrights .
+.It Bq Er ENOTCAPABLE
+.Fa fcntlrights
+would expand the list of allowed
+.Xr fcntl 2
+commands.
+.El
+.Pp
+.Fn cap_fcntls_get
+succeeds unless:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The
+.Fa fd
+argument is not a valid descriptor.
+.It Bq Er EFAULT
+The
+.Fa fcntlrightsp
+argument points at an invalid address.
+.El
+.Sh SEE ALSO
+.Xr cap_ioctls_limit 2 ,
+.Xr cap_rights_limit 2 ,
+.Xr fcntl 2
+.Sh HISTORY
+Support for capabilities and capabilities mode was developed as part of the
+.Tn TrustedBSD
+Project.
+.Sh AUTHORS
+This function was created by
+.An Pawel Jakub Dawidek Aq pawel@dawidek.net
+under sponsorship of the FreeBSD Foundation.