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 Nov 20, 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 cdDeFhinNqvx 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 cdDeFhinNqvx 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 c 61Check if the value will change when assigning a new value. 62If verbose 63.Pq see Dq Fl v 64prints a message stating whether a change would occur. 65Exits with success if no change is necessary, else returns error status. 66.It Fl d 67Print a description of the given variable. 68.It Fl D 69Show default value(s) only (this is the same as setting RC_CONFS to NULL or 70passing `-f' with a NULL file-argument). 71.It Fl e 72Print query results as 73.Xr sh 1 74compatible syntax 75.Pq for example, Ql var=value . 76Ignored if either 77.Ql Fl n 78or 79.Ql Fl F 80is specified. 81.It Fl f Ar file 82Operate on the specified file(s) instead of the files obtained by reading the 83.Sq rc_conf_files 84entry in the 85.Ev RC_DEFAULTS 86file. 87This option can be specified multiple times for additional files. 88.It Fl F 89Show only the last 90.Xr rc.conf 5 91file each directive is in. 92.It Fl h 93Print a short usage message to stderr and exit. 94.It Fl -help 95Print a full usage statement to stderr and exit. 96.It Fl i 97Ignore unknown variables. 98.It Fl j Ar jail 99The 100.Ar jid 101or name of the 102.Ar jail 103to operate within 104.Pq overrides So Fl R Ar dir Sc ; requires Xr jexec 8 . 105.It Fl n 106Show only variable values, not their names. 107.It Fl N 108Show only variable names, not their values. 109.It Fl q 110Quiet. 111Ignore previous occurrences of 112.Fl v 113flag. 114.It Fl R Ar dir 115Operate within the root directory 116.Pq Sq Ar dir 117rather than 118.Pq Sq / . 119.It Fl v 120Verbose. 121Print the pathname of the specific 122.Xr rc.conf 5 123file where the directive was found. 124.It Fl -version 125Print version information to stdout and exit. 126.It Fl x 127Remove variable(s) from specified file(s). 128.El 129.Pp 130This utility works similar to 131.Xr sysctl 8 . 132It shares the `-e' and `-n' options 133.Pq detailed above 134and also has the same 135.Ql name[=value] 136syntax for querying/setting configuration options. 137.Pp 138However, while 139.Xr sysctl 8 140serves to query/modify MIBs in the entrant kernel, 141.Nm 142instead works on values in the system 143.Xr rc.conf 5 144configuration files. 145.Pp 146The list of system configuration files is configured in the file 147.Ql /etc/defaults/rc.conf 148within the variable 149.Ql rc_conf_files , 150which by-default contains a space-separated list of pathnames. 151On all FreeBSD 152systems, this defaults to the value "/etc/rc.conf /etc/rc.conf.local". 153Each 154pathname is sourced in-order upon startup. 155It is in the same fashion that 156.Nm 157sources the configuration files before returning the value of the given 158variable. 159.Pp 160When supplied a variable name, 161.Nm 162will return the value of the variable. 163If the variable does not appear in any 164of the configured 165.Ql rc_conf_files , 166an error is printed and error status is returned. 167.Pp 168When changing values of a given variable, it does not matter if the variable 169appears in any of the 170.Ql rc_conf_files 171or not. 172If the variable does not appear in any of the files, it is appended to 173the end of the first pathname in the 174.Ql rc_conf_files 175variable. 176Otherwise, 177.Nm 178will replace only the last-occurrence in the last-file found to contain the 179variable. 180This gets the value to take effect next boot without heavily 181modifying these integral files (yet taking care not to allow the file to 182grow unwieldy should 183.Nm 184be called repeatedly). 185.Sh ENVIRONMENT 186The following environment variables are referenced by 187.Nm : 188.Bl -tag -width ".Ev RC_DEFAULTS" 189.It Ev RC_CONFS 190Override default 191.Ql rc_conf_files 192.Pq even if set to NULL . 193.It Ev RC_DEFAULTS 194Location of 195.Ql /etc/defaults/rc.conf 196file. 197.El 198.Sh DEPENDENCIES 199The following standard commands are required by 200.Nm : 201.Pp 202.Xr awk 1 , 203.Xr cat 1 , 204.Xr chmod 1 , 205.Xr env 1 , 206.Xr grep 1 , 207.Xr jls 1 , 208.Xr mktemp 1 , 209.Xr mv 1 , 210.Xr rm 1 , 211.Xr sh 1 , 212.Xr stat 1 , 213.Xr tail 1 , 214.Xr chown 8 215and 216.Xr jexec 8 . 217.Sh FILES 218.Bl -tag -width ".Pa /etc/defaults/rc.conf" -compact 219.It Pa /etc/defaults/rc.conf 220.It Pa /etc/rc.conf 221.It Pa /etc/rc.conf.local 222.El 223.Sh EXAMPLES 224Below are some simple examples of how 225.Nm 226can be used to query certain values from the 227.Xr rc.conf 5 228collection of system configuration files: 229.Pp 230.Nm 231sshd_enable 232.Dl returns the value of $sshd_enable, usually YES or NO . 233.Pp 234.Nm 235defaultrouter 236.Dl returns IP address of default router Pq if configured . 237.Pp 238Working on other files, such as 239.Xr crontab 5 : 240.Pp 241.Nm 242-f /etc/crontab MAILTO 243.Dl returns the value of the MAILTO setting Pq if configured . 244.Pp 245In addition to the above syntax, 246.Nm 247also supports inline 248.Xr sh 1 249PARAMETER expansion for changing the way values are reported, shown below: 250.Pp 251.Nm 252\&'hostname%%.*' 253.Dl returns $hostname up to (but not including) first `.' . 254.Pp 255.Nm 256\&'network_interfaces%%[$IFS]*' 257.Dl returns first word of $network_interfaces . 258.Pp 259.Nm 260\&'ntpdate_flags##*[$IFS]' 261.Dl returns last word of $ntpdate_flags (time server address) . 262.Pp 263.Nm 264usbd_flags-"default" 265.Dl returns $usbd_flags or "default" if unset or NULL . 266.Pp 267.Nm 268cloned_interfaces+"alternate" 269.Dl returns "alternate" if $cloned_interfaces is set . 270.Pp 271.Nm 272\&'#kern_securelevel' 273.Dl returns length in characters of $kern_securelevel . 274.Pp 275.Nm 276\&'hostname?' 277.Dl returns NULL and error status 2 if $hostname is unset Pq or if set, returns the value of $hostname with no error status . 278.Pp 279.Nm 280\&'hostname:?' 281.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 . 282.Sh LIMITATIONS 283The 284.Nm 285utility presently does not support the 286.Ql rc.conf.d 287collection of system configuration files 288.Pq which requires a service name to be known during execution . 289.Pp 290This will be corrected by a future enhancement. 291.Sh SEE ALSO 292.Xr jls 1 , 293.Xr rc.conf 5 , 294.Xr jail 8 , 295.Xr jexec 8 , 296.Xr rc 8 , 297.Xr sysctl 8 298.Sh HISTORY 299A 300.Nm 301utility first appeared in 302.Fx 9.2 . 303.Sh AUTHORS 304.An Devin Teske Aq dteske@FreeBSD.org 305.Sh THANKS TO 306Brandon Gooch, Garrett Cooper, Julian Elischer, Pawel Jakub Dawidek, 307Cyrille Lefevre, Ross West, Stefan Esser, Marco Steinbach, and Jilles Tjoelker 308for suggestions and help. 309