209 lines
6.7 KiB
Groff
209 lines
6.7 KiB
Groff
.\" Copyright (c) 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" 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.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
|
|
.\"
|
|
.\" @(#)sysctl.8 8.1 (Berkeley) 6/6/93
|
|
.\"
|
|
.Dd "June 6, 1993"
|
|
.Dt SYSCTL 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm sysctl
|
|
.Nd get or set kernel state
|
|
.Sh SYNOPSIS
|
|
.Nm sysctl
|
|
.Op Fl n
|
|
.Ar name ...
|
|
.Nm sysctl
|
|
.Op Fl n
|
|
.Fl w
|
|
.Ar name=value ...
|
|
.Nm sysctl
|
|
.Op Fl n
|
|
.Fl aA
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm sysctl
|
|
utility retrieves kernel state and allows processes with
|
|
appropriate privilege to set kernel state.
|
|
The state to be retrieved or set is described using a
|
|
``Management Information Base'' (``MIB'') style name,
|
|
described as a dotted set of components.
|
|
The
|
|
.Fl a
|
|
flag can be used to list all the currently available string or integer values.
|
|
The
|
|
.Fl A
|
|
flag will list all the known MIB names including tables.
|
|
Those with string or integer values will be printed as with the
|
|
.Fl a
|
|
flag; for the table values,
|
|
the name of the utility to retrieve them is given.
|
|
.Pp
|
|
The
|
|
.Fl n
|
|
flag specifies that the printing of the field name should be
|
|
suppressed and that only its value should be output.
|
|
This flag is useful for setting shell variables.
|
|
For example, to save the pagesize in variable psize, use:
|
|
.Bd -literal -offset indent -compact
|
|
set psize=`sysctl -n hw.pagesize`
|
|
.Ed
|
|
.Pp
|
|
If just a MIB style name is given,
|
|
the corresponding value is retrieved.
|
|
If a value is to be set, the
|
|
.Fl w
|
|
flag must be specified and the MIB name followed
|
|
by an equal sign and the new value to be used.
|
|
.Pp
|
|
The information available from
|
|
.Nm sysctl
|
|
consists of integers, strings, and tables.
|
|
The tabular information can only be retrieved by special
|
|
purpose programs such as
|
|
.Nm ps ,
|
|
.Nm systat ,
|
|
and
|
|
.Nm netstat .
|
|
The string and integer information is summaried below.
|
|
For a detailed description of these variable see
|
|
.Xr sysctl 3 .
|
|
The changeable column indicates whether a process with appropriate
|
|
privilege can change the value.
|
|
.Bl -column net.inet.ip.forwardingxxxxxx integerxxx
|
|
.It Sy Name Type Changeable
|
|
.It kern.ostype string no
|
|
.It kern.osrelease string no
|
|
.It kern.osrevision integer no
|
|
.It kern.version string no
|
|
.It kern.maxvnodes integer yes
|
|
.It kern.maxproc integer yes
|
|
.It kern.maxfiles integer yes
|
|
.It kern.argmax integer no
|
|
.It kern.securelevel integer raise only
|
|
.It kern.hostname string yes
|
|
.It kern.hostid integer yes
|
|
.It kern.clockrate struct no
|
|
.It kern.posix1version integer no
|
|
.It kern.ngroups integer no
|
|
.It kern.job_control integer no
|
|
.It kern.saved_ids integer no
|
|
.It kern.link_max integer no
|
|
.It kern.max_canon integer no
|
|
.It kern.max_input integer no
|
|
.It kern.name_max integer no
|
|
.It kern.path_max integer no
|
|
.It kern.pipe_buf integer no
|
|
.It kern.chown_restricted integer no
|
|
.It kern.no_trunc integer no
|
|
.It kern.vdisable integer no
|
|
.It kern.boottime struct no
|
|
.It vm.loadavg struct no
|
|
.It machdep.console_device dev_t no
|
|
.It net.inet.ip.forwarding integer yes
|
|
.It net.inet.ip.redirect integer yes
|
|
.It net.inet.ip.ttl integer yes
|
|
.It net.inet.icmp.maskrepl integer yes
|
|
.It net.inet.udp.checksum integer yes
|
|
.It hw.machine string no
|
|
.It hw.model string no
|
|
.It hw.ncpu integer no
|
|
.It hw.byteorder integer no
|
|
.It hw.physmem integer no
|
|
.It hw.usermem integer no
|
|
.It hw.pagesize integer no
|
|
.It user.cs_path string no
|
|
.It user.bc_base_max integer no
|
|
.It user.bc_dim_max integer no
|
|
.It user.bc_scale_max integer no
|
|
.It user.bc_string_max integer no
|
|
.It user.coll_weights_max integer no
|
|
.It user.expr_nest_max integer no
|
|
.It user.line_max integer no
|
|
.It user.re_dup_max integer no
|
|
.It user.posix2_version integer no
|
|
.It user.posix2_c_bind integer no
|
|
.It user.posix2_c_dev integer no
|
|
.It user.posix2_char_term integer no
|
|
.It user.posix2_fort_dev integer no
|
|
.It user.posix2_fort_run integer no
|
|
.It user.posix2_localedef integer no
|
|
.It user.posix2_sw_dev integer no
|
|
.It user.posix2_upe integer no
|
|
.El
|
|
.Sh EXAMPLES
|
|
.Pp
|
|
For example, to retrieve the maximum number of processes allowed
|
|
in the system, one would use the follow request:
|
|
.Bd -literal -offset indent -compact
|
|
sysctl kern.maxproc
|
|
.Ed
|
|
.Pp
|
|
To set the maximum number of processes allowed
|
|
in the system to 1000, one would use the follow request:
|
|
.Bd -literal -offset indent -compact
|
|
sysctl -w kern.maxproc=1000
|
|
.Ed
|
|
.Pp
|
|
Information about the system clock rate may be obtained with:
|
|
.Bd -literal -offset indent -compact
|
|
sysctl kern.clockrate
|
|
.Ed
|
|
.Pp
|
|
Information about the load average history may be obtained with
|
|
.Bd -literal -offset indent -compact
|
|
sysctl vm.loadavg
|
|
.Ed
|
|
.Sh FILES
|
|
.Bl -tag -width <netinet/icmpXvar.h> -compact
|
|
.It Pa <sys/sysctl.h>
|
|
definitions for top level identifiers, second level kernel and hardware
|
|
identifiers, and user level identifiers
|
|
.It Pa <sys/socket.h>
|
|
definitions for second level network identifiers
|
|
.It Pa <sys/gmon.h>
|
|
definitions for third level profiling identifiers
|
|
.It Pa <vm/vm_param.h>
|
|
definitions for second level virtual memory identifiers
|
|
.It Pa <netinet/in.h>
|
|
definitions for third level Internet identifiers and
|
|
fourth level IP identifiers
|
|
.It Pa <netinet/icmp_var.h>
|
|
definitions for fourth level ICMP identifiers
|
|
.It Pa <netinet/udp_var.h>
|
|
definitions for fourth level UDP identifiers
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr sysctl 3
|
|
.Sh HISTORY
|
|
.Nm sysctl
|
|
first appeared in 4.4BSD.
|