1.\" Copyright (c) 2013 Hudson River Trading LLC 2.\" Written by: John H. Baldwin <jhb@FreeBSD.org> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd September 19, 2013 29.Dt PROTECT 1 30.Os 31.Sh NAME 32.Nm protect 33.Nd "protect processes from being killed when swap space is exhausted" 34.Sh SYNOPSIS 35.Nm 36.Op Fl i 37.Ar command 38.Nm 39.Op Fl cdi 40.Fl g Ar pgrp | Fl p Ar pid 41.Sh DESCRIPTION 42The 43.Nm 44command is used to mark processes as protected. 45The kernel does not kill protected processes when swap space is exhausted. 46Note that this protected state is not inherited by child processes by default. 47.Pp 48The options are: 49.Bl -tag -width XXXXXXXXXX 50.It Fl c 51Remove protection from the specified processes. 52.It Fl d 53Apply the operation to all current children of the specified processes. 54.It Fl i 55Apply the operation to all future children of the specified processes. 56.It Fl g Ar pgrp 57Apply the operation to all processes in the specified process group. 58.It Fl p Ar pid 59Apply the operation to the specified process. 60.It Ar command 61Execute 62.Ar command 63as a protected process. 64.El 65.Pp 66Note that only one of the 67.Fl p 68or 69.Fl g 70flags may be specified when adjusting the state of existing processes. 71.Sh EXIT STATUS 72.Ex -std 73.Sh EXAMPLES 74Mark the Xorg server as protected: 75.Pp 76.Dl "pgrep Xorg | xargs protect -p" 77.Pp 78Protect all ssh sessions and their child processes: 79.Pp 80.Dl "pgrep sshd | xargs protect -dip" 81.Pp 82Remove protection from all current and future processes: 83.Pp 84.Dl "protect -cdi -p 1" 85.Sh SEE ALSO 86.Xr procctl 2 87.Sh BUGS 88If you protect a runaway process that allocates all memory the system will 89deadlock. 90