1.\" Copyright (c) 2011-2013 Devin Teske 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd Jul 5, 2013 28.Dt SYSRC 8 29.Os 30.Sh NAME 31.Nm sysrc 32.Nd safely edit system rc files 33.Sh SYNOPSIS 34.Nm 35.Op Fl dDeFhinNqvx 36.Op Fl f Ar file 37.Op Fl j Ar jail | Fl R Ar dir 38.Ar name Ns Op = Ns Ar value 39.Ar ... 40.Nm 41.Op Fl dDeFhinNqvx 42.Op Fl f Ar file 43.Op Fl j Ar jail | Fl R Ar dir 44.Fl a | A 45.Sh DESCRIPTION 46The 47.Nm 48utility retrieves 49.Xr rc.conf 5 50variables from the collection of system rc files and allows processes with 51appropriate privilege to change values in a safe and effective manner. 52.Pp 53The following options are available: 54.Bl -tag -width indent+ 55.It Fl a 56Dump a list of all non-default configuration variables. 57.It Fl A 58Dump a list of all configuration variables 59.Pq incl. defaults . 60.It Fl d 61Print a description of the given variable. 62.It Fl D 63Show default value(s) only (this is the same as setting RC_CONFS to NULL or 64passing `-f' with a NULL file-argument). 65.It Fl e 66Print query results as 67.Ql var=value 68.Pq useful for producing output to be fed back in . 69Ignored if 70.Fl n 71is specified. 72.It Fl f Ar file 73Operate on the specified file(s) instead of the files obtained by reading the 74.Sq rc_conf_files 75entry in the 76.Ev RC_DEFAULTS 77file. 78This option can be specified multiple times for additional files. 79.It Fl F 80Show only the last 81.Xr rc.conf 5 82file each directive is in. 83.It Fl h 84Print a short usage message to stderr and exit. 85.It Fl -help 86Print a full usage statement to stderr and exit. 87.It Fl i 88Ignore unknown variables. 89.It Fl j Ar jail 90The 91.Ar jid 92or name of the 93.Ar jail 94to operate within 95.Pq overrides So Fl R Ar dir Sc ; requires Xr jexec 8 . 96.It Fl n 97Show only variable values, not their names. 98.It Fl N 99Show only variable names, not their values. 100.It Fl q 101Quiet. 102Ignore previous occurrences of 103.Fl v 104flag. 105.It Fl R Ar dir 106Operate within the root directory 107.Pq Sq Ar dir 108rather than 109.Pq Sq / . 110.It Fl v 111Verbose. 112Print the pathname of the specific 113.Xr rc.conf 5 114file where the directive was found. 115.It Fl x 116Remove variable(s) from specified file(s). 117.El 118.Pp 119This utility works similar to 120.Xr sysctl 8 . 121It shares the `-e' and `-n' options 122.Pq detailed above 123and also has the same 124.Ql name[=value] 125syntax for querying/setting configuration options. 126.Pp 127However, while 128.Xr sysctl 8 129serves to query/modify MIBs in the entrant kernel, 130.Nm 131instead works on values in the system 132.Xr rc.conf 5 133configuration files. 134.Pp 135The list of system configuration files is configured in the file 136.Ql /etc/defaults/rc.conf 137within the variable 138.Ql rc_conf_files , 139which by-default contains a space-separated list of pathnames. 140On all FreeBSD 141systems, this defaults to the value "/etc/rc.conf /etc/rc.conf.local". 142Each 143pathname is sourced in-order upon startup. 144It is in the same fashion that 145.Nm 146sources the configuration files before returning the value of the given 147variable. 148.Pp 149When supplied a variable name, 150.Nm 151will return the value of the variable. 152If the variable does not appear in any 153of the configured 154.Ql rc_conf_files , 155an error is printed and error status is returned. 156.Pp 157When changing values of a given variable, it does not matter if the variable 158appears in any of the 159.Ql rc_conf_files 160or not. 161If the variable does not appear in any of the files, it is appended to 162the end of the first pathname in the 163.Ql rc_conf_files 164variable. 165Otherwise, 166.Nm 167will replace only the last-occurrence in the last-file found to contain the 168variable. 169This gets the value to take effect next boot without heavily 170modifying these integral files (yet taking care not to allow the file to 171grow unwieldy should 172.Nm 173be called repeatedly). 174.Sh ENVIRONMENT 175The following environment variables are referenced by 176.Nm : 177.Bl -tag -width ".Ev RC_DEFAULTS" 178.It Ev RC_CONFS 179Override default 180.Ql rc_conf_files 181.Pq even if set to NULL . 182.It Ev RC_DEFAULTS 183Location of 184.Ql /etc/defaults/rc.conf 185file. 186.El 187.Sh DEPENDENCIES 188The following standard commands are required by 189.Nm : 190.Pp 191.Xr awk 1 , 192.Xr cat 1 , 193.Xr chmod 1 , 194.Xr env 1 , 195.Xr grep 1 , 196.Xr jls 1 , 197.Xr mktemp 1 , 198.Xr mv 1 , 199.Xr rm 1 , 200.Xr sh 1 , 201.Xr stat 1 , 202.Xr tail 1 , 203.Xr chown 8 204and 205.Xr jexec 8 . 206.Sh FILES 207.Bl -tag -width ".Pa /etc/defaults/rc.conf" -compact 208.It Pa /etc/defaults/rc.conf 209.It Pa /etc/rc.conf 210.It Pa /etc/rc.conf.local 211.El 212.Sh EXAMPLES 213Below are some simple examples of how 214.Nm 215can be used to query certain values from the 216.Xr rc.conf 5 217collection of system configuration files: 218.Pp 219.Nm 220sshd_enable 221.Dl returns the value of $sshd_enable, usually YES or NO . 222.Pp 223.Nm 224defaultrouter 225.Dl returns IP address of default router Pq if configured . 226.Pp 227Working on other files, such as 228.Xr crontab 5 : 229.Pp 230.Nm 231-f /etc/crontab MAILTO 232.Dl returns the value of the MAILTO setting Pq if configured . 233.Pp 234In addition to the above syntax, 235.Nm 236also supports inline 237.Xr sh 1 238PARAMETER expansion for changing the way values are reported, shown below: 239.Pp 240.Nm 241\&'hostname%%.*' 242.Dl returns $hostname up to (but not including) first `.' . 243.Pp 244.Nm 245\&'network_interfaces%%[$IFS]*' 246.Dl returns first word of $network_interfaces . 247.Pp 248.Nm 249\&'ntpdate_flags##*[$IFS]' 250.Dl returns last word of $ntpdate_flags (time server address) . 251.Pp 252.Nm 253usbd_flags-"default" 254.Dl returns $usbd_flags or "default" if unset or NULL . 255.Pp 256.Nm 257cloned_interfaces+"alternate" 258.Dl returns "alternate" if $cloned_interfaces is set . 259.Pp 260.Nm 261\&'#kern_securelevel' 262.Dl returns length in characters of $kern_securelevel . 263.Pp 264.Nm 265\&'hostname?' 266.Dl returns NULL and error status 2 if $hostname is unset Pq or if set, returns the value of $hostname with no error status . 267.Pp 268.Nm 269\&'hostname:?' 270.Dl returns NULL and error status 2 if $hostname is unset or NULL Pq or if set and non-NULL, returns value without error status . 271.Sh LIMITATIONS 272The 273.Nm 274utility presently does not support the 275.Ql rc.conf.d 276collection of system configuration files 277.Pq which requires a service name to be known during execution . 278.Pp 279This will be corrected by a future enhancement. 280.Sh SEE ALSO 281.Xr jls 1 , 282.Xr rc.conf 5 , 283.Xr jail 8 , 284.Xr jexec 8 , 285.Xr rc 8 , 286.Xr sysctl 8 287.Sh HISTORY 288A 289.Nm 290utility first appeared in 291.Fx 10.0 . 292.Sh AUTHORS 293.An Devin Teske Aq dteske@FreeBSD.org 294.Sh THANKS TO 295Brandon Gooch, Garrett Cooper, Julian Elischer, Pawel Jakub Dawidek, 296Cyrille Lefevre, Ross West, Stefan Esser, Marco Steinbach, and Jilles Tjoelker 297for suggestions and help. 298