NAME

SYNOPSIS

DESCRIPTION

int mib[2], maxproc;
size_t len;

mib[0] = CTL_KERN;
mib[1] = KERN_MAXPROC;
len = sizeof(maxproc);
if (sysctl(mib, 2, &maxproc, &len, NULL, 0) == -1)
	err(1, "sysctl");

int mib[2];
size_t len;
char *p;

mib[0] = CTL_USER;
mib[1] = USER_CS_PATH;
if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1)
	err(1, "sysctl");
if ((p = malloc(len)) == NULL)
	err(1, NULL);
if (sysctl(mib, 2, p, &len, NULL, 0) == -1)
	err(1, "sysctl");

CTL_DDB

DBCTL_CONSOLE

When this variable is set, an architecture dependent magic key sequence on the console or a debugger button will permit entry into the kernel debugger. When running with a securelevel(7) greater than 0, this variable may not be raised.

DBCTL_LOG

When set, ddb output is also logged in the kernel message buffer.

DBCTL_MAXLINE

Determines the number of lines to page in ddb(4). This variable is also available as the ddb $lines variable.

DBCTL_MAXWIDTH

Determines the maximum width of a line in ddb(4). This variable is also available as the ddb $maxwidth variable.

DBCTL_PANIC

When this variable is set, system panics may drop into the kernel debugger. When running with a securelevel(7) greater than 0, this variable may not be raised.

DBCTL_RADIX

Determines the default radix or base for non-prefixed numbers entered into ddb(4). This variable is also available as the ddb $radix variable.

DBCTL_TABSTOP

Width of a tab stop in ddb(4). This variable is also available as the ddb $tabstops variable.

DBCTL_TRIGGER

When DBCTL_CONSOLE is set, writing to DBCTL_TRIGGER causes the system to enter ddb(4). If securelevel(7) is greater than 0, the process writing to this variable must be running on the console in order to enter ddb(4).

CTL_DEBUG

int dospecialcheck = 1;
struct ctldebug debug5 = { "dospecialcheck", &dospecialcheck };

CTL_FS

FS_POSIX_SETUID

When this variable is set, ownership changes on a file will cause the S_ISUID and S_ISGID bits to be cleared. As detailed in securelevel(7), this variable may not be changed if the securelevel is \*(Gt 0.

CTL_HW

HW_BYTEORDER

The byteorder (4321 or 1234).

HW_CPUSPEED

The current CPU frequency (in MHz).

HW_DISKCOUNT

The number of disks currently attached to the system.

HW_DISKNAMES

A comma-separated list of disk names.

HW_DISKSTATS

An array of struct diskstats structures containing disk statistics.

HW_MACHINE

The machine class.

HW_MODEL

The machine model.

HW_NCPU

The number of CPUs.

HW_PAGESIZE

The software page size.

HW_PHYSMEM

The total physical memory, in bytes. This variable is deprecated; use HW_PHYSMEM64 instead.

HW_PHYSMEM64

The total physical memory, in bytes.

HW_PRODUCT

The product name of the machine.

HW_SENSORS

Third level comprises an array of struct sensordev structures containing information about devices that may attach hardware monitoring sensors.

Third, fourth and fifth levels together comprise an array of struct sensor structures containing snapshot readings of hardware monitoring sensors. In such usage, third level indicates the numerical representation of the sensor device name to which the sensor is attached (a device's xname and number are matched with the help of struct sensordev structure above), fourth level indicates sensor type and fifth level is an ordinal sensor number (unique to the specified sensor type on the specified sensor device).

The sensordev and sensor structures and sensor_type enumeration are defined in ‹sys/sensors.h›.

HW_SERIALNO

The serial number of the machine.

HW_SETPERF

Current CPU performance (percentage).

HW_USERMEM

The amount of available non-kernel memory in bytes. This variable is deprecated; use HW_USERMEM64 instead.

HW_USERMEM64

The amount of available non-kernel memory in bytes.

HW_UUID

The universal unique identification number assigned to the machine.

HW_VENDOR

The vendor name for this machine.

HW_VERSION

The version or revision of this machine.

CTL_KERN

KERN_ARGMAX

The maximum number of bytes allowed among the arguments to exec(3).

KERN_ARND

Returns a maximum of 256 random bytes from the kernel using the arc4random(9) function. This can be useful if /dev/arandom is not available (see random(4/)).

KERN_BOOTTIME

A struct timeval structure is returned. This structure contains the time that the system was booted.

KERN_CCPU

The scheduler exponential decay value.

KERN_CLOCKRATE

A struct clockinfo structure is returned. This structure contains the clock, statistics clock and profiling clock frequencies, the number of micro-seconds per hz tick, and the clock skew rate.

KERN_CPTIME

An array of longs of size CPUSTATES is returned, containing statistics about the number of ticks spent by the system among all processors in interrupt processing, user processes ( nice(1) or normal ), system processing, or idling.

KERN_CPTIME2

Similar to KERN_CPTIME, but obtains information from only the single CPU specified by the third level name given.

KERN_CRYPTODEVALLOWSOFT

Permits userland to use /dev/crypto even if there is no hardware crypto accelerator in the system.

KERN_DOMAINNAME

Get or set the YP domain name.

KERN_DUMPDEV

KERN_DUMPLO

KERN_DUMPMAG

System crash dump (see savecore(8)) information, consisting of dump device number, block offset for starting the dump, dump magic pattern. The “dump device” is usually set at boot time to the same number as .Dr swap device (see KERN_ROOTDEV below).

KERN_EMUL

Enable binary emulation.

Third level name	Type	Changeable
KERN_EMUL_ENABLED	integer	yes
KERN_EMUL_NAME	string	no
KERN_EMUL_NEMULS	integer	no

Third level names in KERN_EMUL other than KERN_EMUL_NEMULS refer to a specific emulation available in the kernel. Valid values range from 1 to the return value of KERN_EMUL_NEMULS. The fourth level names available are KERN_EMUL_NAME, which returns a string with the emulation name, and KERN_EMUL_ENABLED, which is an adjustable integer.

Note that using this interface exposes duplicate entries which are consolidated by the userland frontend.

KERN_FILE

Return the entire file table. The returned data consists of a single struct filehead followed by an array of struct file, whose size depends on the current number of such objects in the system.

KERN_FORKSTAT

A struct forkstat structure is returned. This structure contains information about the number of fork(2), vfork(2), and rfork(2) system calls as well as kernel thread creations since system startup, and the number of pages of virtual memory involved in each.

KERN_FSCALE

The kernel fixed-point scale factor.

KERN_FSYNC

Return 1 if the File Synchronisation Option is available on this system, otherwise 0.

KERN_HOSTID

Get or set the host ID.

KERN_HOSTNAME

Get or set the hostname.

KERN_JOB_CONTROL

Return 1 if job control is available on this system, otherwise 0.

KERN_MALLOCSTATS

Return kernel memory bucket statistics. The third level names are detailed below. There are no changeable values in this branch.

Third level name		Type
KERN_MALLOC_BUCKET		node
KERN_MALLOC_BUCKETS		string
KERN_MALLOC_KMEMNAMES		string
KERN_MALLOC_KMEMSTATS		node

The variables are as follows:

KERN_MALLOC_BUCKET.\*(Ltsize\*(Gt

A node containing the statistics for the memory bucket of the specified size (in decimal notation, the number of bytes per bucket element, e.g., 16, 32, 128). Each node returns a struct kmembuckets.

If a value is specified that does not correspond directly to a bucket size, the statistics for the closest larger bucket size will be returned instead.

Note that bucket sizes are typically powers of 2.

KERN_MALLOC_BUCKETS

Return a comma-separated list of the bucket sizes used by the kernel.

KERN_MALLOC_KMEMNAMES

Return a comma-separated list of the names of the kernel malloc(9) types.

KERN_MALLOC_KMEMSTATS

A node containing the statistics for the memory types of the specified name. Each node returns a struct kmemstats.

KERN_MAXCLUSTERS

The maximum number of mbuf(9) clusters that may be allocated.

KERN_MAXFILES

The maximum number of open files that may be open in the system.

KERN_MAXPARTITIONS

The maximum number of partitions allowed per disk.

KERN_MAXPROC

The maximum number of simultaneous processes the system will allow.

KERN_MAXVNODES

The maximum number of vnodes available on the system.

KERN_MBSTAT

A struct mbstat structure is returned, containing statistics on mbuf(9) usage.

KERN_MSGBUF

Returns a buffer containing kernel log messages.

KERN_MSGBUFSIZE

The size of the kernel message buffer.

KERN_NCHSTATS

A struct nchstats structure is returned. This structure contains information about the filename to inode(5) mapping cache.

KERN_NFILES

Number of open files.

KERN_NGROUPS

The maximum number of supplemental groups.

KERN_NOSUIDCOREDUMP

Programs with their set-user-ID bit set will not dump core when this is set. The special value of 2 means that core dumps will be allowed, but placed in /var/crash.

KERN_NPROCS

The number of entries in the kernel process table.

KERN_NSELCOLL

Number of select(2) collisions.

KERN_NUMVNODES

Number of vnodes in use.

KERN_OSRELEASE

The system release string.

KERN_OSREV

The system revision number.

KERN_OSTYPE

The system type string.

KERN_OSVERSION

The kernel build version.

KERN_POSIX1

The version of ISO/IEC 9945 (POSIX 1003.1) with which the system attempts to comply.

KERN_PROC

Return the entire process table, or a subset of it. An array of struct kinfo_proc structures is returned, whose size depends on the current number of such objects in the system. The third and fourth level names are as follows:

Third level name	Fourth level is:
KERN_PROC_ALL	None
KERN_PROC_KTHREAD	A kernel thread
KERN_PROC_PID	A process ID
KERN_PROC_PGRP	A process group
KERN_PROC_RUID	A real user ID
KERN_PROC_SESSION	A session PID
KERN_PROC_TTY	A tty device
KERN_PROC_UID	A user ID

KERN_PROC2

Like KERN_PROC but an array of struct kinfo_proc2 structures is returned. The fifth level name is the size of the struct kinfo_proc2 and the sixth level name is the number of structures to return.

KERN_PROC_ARGS

Returns the arguments or environment of a process. The third level name is the PID of the process. The fourth level name is one of:

KERN_PROC_ARGV

KERN_PROC_ENV

KERN_PROC_NARGV

KERN_PROC_NENV

KERN_PROC_NARGV and KERN_PROC_NENV return the number of elements as an int in the argv or env array. KERN_PROC_ARGV returns the argv array and KERN_PROC_ENV returns the environ array.

KERN_PROF

Return profiling information about the kernel. If the kernel is not compiled for profiling, attempts to retrieve any of the KERN_PROF values will fail with EOPNOTSUPP. The third level names for the string and integer profiling information are detailed below. The changeable column shows whether a process with appropriate privileges may change the value.

Third level name	Type	Changeable
GPROF_COUNT	u_short[]	yes
GPROF_FROMS	u_short[]	yes
GPROF_GMONPARAM	struct gmonparam	no
GPROF_STATE	integer	yes
GPROF_TOS	struct tostruct	yes

The variables are as follows:

GPROF_COUNT

Array of statistical program counter counts.

GPROF_FROMS

Array indexed by program counter of call-from points.

GPROF_GMONPARAM

Structure giving the sizes of the above arrays.

GPROF_STATE

Returns GMON_PROF_ON or GMON_PROF_OFF to show that profiling is running or stopped.

GPROF_TOS

Array of struct tostruct describing destination of calls and their counts.

KERN_RAWPARTITION

The raw partition of a disk (a == 0).

KERN_RND

Returns statistics about the /dev/random device in a struct rndstats structure.

KERN_ROOTDEV

System “root device” number as set at boot time.

KERN_SAVED_IDS

Returns 1 if saved set-group-ID and saved set-user-ID are available.

KERN_SECURELVL

The system security level. This level may be raised by processes with appropriate privileges. It may only be lowered by process 1.

KERN_SEMINFO

Return the elements of struct seminfo. If the kernel is not compiled with System V style semaphore support, attempts to retrieve any of the KERN_SEMINFO values will fail with EOPNOTSUPP. The third level names for the elements of struct seminfo are detailed below. The changeable column shows whether a process with appropriate privileges may change the value.

Third level name	Type	Changeable
KERN_SEMINFO_SEMAEM	integer	no
KERN_SEMINFO_SEMMNI	integer	yes
KERN_SEMINFO_SEMMNS	integer	yes
KERN_SEMINFO_SEMMNU	integer	yes
KERN_SEMINFO_SEMMSL	integer	yes
KERN_SEMINFO_SEMOPM	integer	yes
KERN_SEMINFO_SEMUME	integer	no
KERN_SEMINFO_SEMUSZ	integer	no
KERN_SEMINFO_SEMVMX	integer	no

The variables are as follows:

KERN_SEMINFO_SEMAEM

The adjust on exit maximum value.

KERN_SEMINFO_SEMMNI

The maximum number of semaphore identifiers allowed.

KERN_SEMINFO_SEMMNS

The maximum number of semaphores allowed in the system.

KERN_SEMINFO_SEMMNU

The maximum number of semaphore undo structures allowed in the system.

KERN_SEMINFO_SEMMSL

The maximum number of semaphores allowed per ID.

KERN_SEMINFO_SEMOPM

The maximum number of operations per semop(2) call.

KERN_SEMINFO_SEMUME

The maximum number of undo entries per process.

KERN_SEMINFO_SEMUSZ

The size (in bytes) of the undo structure.

KERN_SEMINFO_SEMVMX

The semaphore maximum value.

KERN_SHMINFO

Return the elements of struct shminfo. If the kernel is not compiled with System V style shared memory support, attempts to retrieve any of the KERN_SHMINFO values will fail with EOPNOTSUPP. The third level names for the elements of struct shminfo are detailed below. The changeable column shows whether a process with appropriate privileges may change the value.

Third level name	Type	Changeable
KERN_SHMINFO_SHMALL	integer	yes
KERN_SHMINFO_SHMMAX	integer	yes
KERN_SHMINFO_SHMMIN	integer	yes
KERN_SHMINFO_SHMMNI	integer	yes
KERN_SHMINFO_SHMSEG	integer	yes

The variables are as follows:

KERN_SHMINFO_SHMALL

The maximum amount of total shared memory allowed in the system (in pages).

KERN_SHMINFO_SHMMAX

The maximum shared memory segment size (in bytes).

KERN_SHMINFO_SHMMIN

The minimum shared memory segment size (in bytes).

KERN_SHMINFO_SHMMNI

The maximum number of shared memory identifiers in the system.

KERN_SHMINFO_SHMSEG

The maximum number of shared memory segments per process.

KERN_SOMAXCONN

Upper bound on the number of half-open connections a process can allow to be associated with a socket, using listen(2). The default value is 128.

KERN_SOMINCONN

Lower bound on the number of half-open connections a process can allow to be associated with a socket, using listen(2). The default value is 80.

KERN_SPLASSERT

Modify the system interrupt priority level. Valid values are:

0

Disable error checking.

1

Print a message if an error is detected.

2

Print a message if an error is detected, and a stack trace if possible.

3

The same as 2, but also drop into the kernel debugger.

Any other value causes a system panic on errors. See splassert(9) for more information.

KERN_STACKGAPRANDOM

Sets the range of the random value added to the stack pointer on each program execution. The random value is added to make buffer overflow exploitation slightly harder. The bigger the number, the harder it is to brute force this added protection, but it also means bigger waste of memory.

KERN_SWAPDEV

System default “swap device” number as set at boot time.

KERN_SYSVIPC_INFO

Return System V style IPC configuration and run-time information. The third level name selects the System V style IPC facility.

Third level name	Type
KERN_SYSVIPC_MSG_INFO	struct msg_sysctl_info
KERN_SYSVIPC_SEM_INFO	struct sem_sysctl_info
KERN_SYSVIPC_SHM_INFO	struct shm_sysctl_info

KERN_SYSVIPC_MSG_INFO

Return information on the System V style message facility. The msg_sysctl_info structure is defined in ‹sys/msg.h›.

KERN_SYSVIPC_SEM_INFO

Return information on the System V style semaphore facility. The sem_sysctl_info structure is defined in ‹sys/sem.h›.

KERN_SYSVIPC_SHM_INFO

Return information on the System V style shared memory facility. The shm_sysctl_info structure is defined in ‹sys/shm.h›.

KERN_SYSVMSG

Returns 1 if System V style message queue functionality is available on this system, otherwise 0.

KERN_SYSVSEM

Returns 1 if System V style semaphore functionality is available on this system, otherwise 0.

KERN_SYSVSHM

Returns 1 if System V style shared memory functionality is available on this system, otherwise 0.

KERN_TIMECOUNTER

Return statistics information about the kernel time counter. The third level names information is detailed below. The changeable column shows whether a process with appropriate privileges may change the value.

Third level name	Type	Changeable
KERN_TIMECOUNTER_CHOICE	string	no
KERN_TIMECOUNTER_HARDWARE	string	yes
KERN_TIMECOUNTER_TICK	integer	no
KERN_TIMECOUNTER_TIMESTEPWARNINGS	integer	yes

The variables are as follows:

KERN_TIMECOUNTER_CHOICE

Get the list of kernel time counter sources and their claimed quality (higher is better).

KERN_TIMECOUNTER_HARDWARE

Get or set the kernel time counter source by name.

KERN_TIMECOUNTER_TICK

Get the number of times we have reset the kernel time counter information.

KERN_TIMECOUNTER_TIMESTEPWARNINGS

Get or set a flag to log a message when the kernel time is stepped.

KERN_TTY

Return statistics information about tty input/output. The third level names information is detailed below. The changeable column shows whether a process with appropriate privileges may change the value.

Third level name	Type	Changeable
KERN_TTY_INFO	struct itty	no
KERN_TTY_NPTYS	integer	no
KERN_TTY_MAXPTYS	integer	yes
KERN_TTY_TKCANCC	int64_t	no
KERN_TTY_TKNIN	int64_t	no
KERN_TTY_TKNOUT	int64_t	no
KERN_TTY_TKRAWCC	int64_t	no

The variables are as follows:

KERN_TTY_INFO

Returns an array of struct itty structures containing tty statistics.

KERN_TTY_MAXPTYS

The maximum number of pty(4) devices supported by the kernel. This is the upper bound on KERN_TTY_NPTYS.

KERN_TTY_NPTYS

The current number of pty(4) devices allocated by the kernel.

KERN_TTY_TKCANCC

Returns the number of input characters in canonical mode.

KERN_TTY_TKNIN

Returns the number of input characters from a tty(4).

KERN_TTY_TKNOUT

Returns the number of output characters on a tty(4).

KERN_TTY_TKRAWCC

Returns the number of input characters in raw mode.

KERN_TTYCOUNT

Number of available tty(4) devices.

KERN_USERASYMCRYPTO

Permits userland to use /dev/crypto for cryptographic support for asymmetric (public) key operations via hardware cryptographic devices. KERN_USERCRYPTO (see below) must also be set.

KERN_USERCRYPTO

Permits userland to use /dev/crypto for cryptographic support via hardware cryptographic devices.

KERN_USERMOUNT

Return non-zero if regular users can issue mount(2) requests. The default value is 0.

KERN_VERSION

The system version string.

KERN_VNODE

Return the entire vnode table. Note, the vnode table is not necessarily a consistent snapshot of the system. The returned data consists of an array whose size depends on the current number of such objects in the system. Each element of the array contains the kernel address of a vnode (struct vnode *) followed by the vnode itself (struct vnode).

KERN_WATCHDOG

Return information on hardware watchdog timers. If the kernel does not support a hardware watchdog timer, attempts to retrieve or set any of the KERN_WATCHDOG values will fail with EOPNOTSUPP.

Third level name	Type	Changeable
KERN_WATCHDOG_AUTO	integer	yes
KERN_WATCHDOG_PERIOD	integer	yes

The variables are as follows:

KERN_WATCHDOG_AUTO

If set to 1, the kernel refreshes the watchdog timer periodically. If set to 0, a userland process must ensure that the watchdog timer gets refreshed by setting the KERN_WATCHDOG_PERIOD variable.

KERN_WATCHDOG_PERIOD

The period of the watchdog timer in seconds. Set to 0 to disable the watchdog timer.

CTL_MACHDEP

CTL_NET

PF_ROUTE

Return the entire routing table or a subset of it. The data is returned as a sequence of routing messages (see route(4) for the header file, format, and meaning). The length of each message is contained in the message header.

The third level name is a protocol number, which is currently always 0. The fourth level name is an address family, which may be set to 0 to select all address families. The fifth and sixth level names are as follows:

Fifth level name	Sixth level is:
NET_RT_DUMP	None
NET_RT_FLAGS	rtflags
NET_RT_IFLIST	None
NET_RT_STATS	None

An optional seventh level name can be provided to select the routing table on which to run the operation. If not provided, the table with ID 0 is used.

PF_INET

Get or set various global information about IPv4 (Internet Protocol version 4). The third level name is the protocol. The fourth level name is the variable name. The currently defined protocols and names are:

Protocol name	Variable name	Type	Changeable
ah	enable	integer	yes
bpf	bufsize	integer	yes
bpf	maxbufsize	integer	yes
carp	allow	integer	yes
carp	log	integer	yes
carp	preempt	integer	yes
esp	enable	integer	yes
esp	udpencap	integer	yes
esp	udpencap_port	integer	yes
etherip	allow	integer	yes
gre	allow	integer	yes
gre	wccp	integer	yes
icmp	bmcastecho	integer	yes
icmp	errppslimit	integer	yes
icmp	maskrepl	integer	yes
icmp	rediraccept	integer	yes
icmp	redirtimeout	integer	yes
icmp	stats	structure	no
icmp	tstamprepl	integer	yes
ip	directed-broadcast	integer	yes
ip	encdebug	integer	yes
ip	forwarding	integer	yes
ip	ipsec-allocs	integer	yes
ip	ipsec-auth-alg	string	yes
ip	ipsec-bytes	integer	yes
ip	ipsec-comp-alg	string	yes
ip	ipsec-enc-alg	string	yes
ip	ipsec-expire-acquire	integer	yes
ip	ipsec-firstuse	integer	yes
ip	ipsec-invalid-life	integer	yes
ip	ipsec-pfs	integer	yes
ip	ipsec-soft-allocs	integer	yes
ip	ipsec-soft-bytes	integer	yes
ip	ipsec-soft-firstuse	integer	yes
ip	ipsec-soft-timeout	integer	yes
ip	ipsec-timeout	integer	yes
ip	maxqueue	integer	yes
ip	mforwarding	integer	yes
ip	mtudisc	integer	yes
ip	mtudisctimeout	integer	yes
ip	multipath	integer	yes
ip	portfirst	integer	yes
ip	porthifirst	integer	yes
ip	porthilast	integer	yes
ip	portlast	integer	yes
ip	redirect	integer	yes
ip	sourceroute	integer	yes
ip	stats	structure	no
ip	ttl	integer	yes
ipcomp	enable	integer	yes
ipip	allow	integer	yes
mobileip	allow	integer	yes
tcp	ackonpush	integer	yes
tcp	baddynamic	array	yes
tcp	ecn	integer	yes
tcp	ident	structure	no
tcp	keepidle	integer	yes
tcp	keepinittime	integer	yes
tcp	keepintvl	integer	yes
tcp	mssdflt	integer	yes
tcp	reasslimit	integer	yes
tcp	recvspace	integer	yes
tcp	rfc1323	integer	yes
tcp	rfc3390	integer	yes
tcp	rstppslimit	integer	yes
tcp	sack	integer	yes
tcp	sendspace	integer	yes
tcp	slowhz	integer	no
tcp	stats	structure	no
tcp	synbucketlimit	integer	yes
tcp	syncachelimit	integer	yes
udp	baddynamic	array	yes
udp	checksum	integer	yes
udp	recvspace	integer	yes
udp	sendspace	integer	yes
udp	stats	structure	no

The variables are as follows:

ah.enable

If set to 1, enable the Authentication Header (AH) IPsec protocol. Enabled by default. See ipsec(4) for more information.

bpf.bufsize

The initial size of bpf(4) buffers.

bpf.maxbufsize

The maximum size a user may request a bpf(4) buffer to be.

carp.allow

If set to 0, incoming carp(4) packets will not be processed. If set to any other value, processing will occur. Enabled by default.

carp.log

Controls the verbosity of carp(4) logging. May be a value between 0 and 7 corresponding with syslog(3) priorities. The default value is 2.

carp.preempt

If set to 0, carp(4) will not attempt to become master if it is receiving advertisements from another active master. If set to any other value, carp will become master of the virtual host if it believes it can send advertisements more frequently than the current master. Disabled by default.

esp.enable

If set to 1, enable the Encapsulating Security Payload (ESP) IPsec protocol. Enabled by default. See ipsec(4) for more information.

esp.udpencap

If set to 1, enable processing of UDP encapsulated ESP packets. Enabled by default.

esp.udpencap_port

Contains the value of the UDP port that triggers decapsulation for incoming UDP encapsulated ESP packets. The default port is 4500.

etherip.allow

If set to 0, incoming Ethernet-in-IPv4 packets will not be processed. If set to any other value, processing will occur.

gre.allow

If set to 0, incoming GRE packets will not be processed. If set to any other value, processing will occur.

gre.wccp

If set to 0, incoming WCCPv1-style GRE packets will not be processed. If set to any other value, and gre.allow allows GRE packet processing, WCCPv1-style GRE packets will be processed.

icmp.bmcastecho

If set to 1, respond to ICMP echo requests destined for broadcast and multicast addresses. Note, enabling this could open a system to a type of denial of service attack called "smurfing", and is thus not advised.

icmp.errppslimit

This variable specifies the maximum number of outgoing ICMP error messages per second. ICMP error messages exceeding this value are subject to rate limitation and will not go out from the node. A negative value disables rate limitation.

icmp.maskrepl

Returns 1 if ICMP network mask requests are to be answered.

icmp.rediraccept

If set to non-zero, the host will accept ICMP redirect packets. Note that routers will never accept ICMP redirect packets, and the variable is meaningful on IP hosts only.

icmp.redirtimeout

This variable specifies the lifetime of routing entries generated by incoming ICMP redirects. The default timeout is 10 minutes.

icmp.stats

Returns the ICMP statistics in a struct icmpstat.

icmp.tstamprepl

If set to 1, reply to ICMP timestamp requests. If set to 0, ignore timestamp requests.

ip.directed-broadcast

Returns 1 if directed broadcast behavior is enabled for the host.

ip.encdebug

Returns 1 when error message reporting is enabled for the host. If the kernel has been compiled with the ENCDEBUG option, then debugging information will also be reported when this variable is set.

ip.forwarding

If set to 1, then IP forwarding is enabled for the host, indicating the host is acting as a router. If set to 2, then IP forwarding is restricted to traffic that has been IPsec encapsulated or decapsulated by the host. The default value is 0.

ip.ipsec-allocs

The number of IPsec flows that can use a security association before it expires. If set to less than or equal to zero, the security association will not expire because of this counter. The default value is 0.

ip.ipsec-auth-alg

This is the default authentication algorithm the kernel will instruct key management daemons to negotiate when establishing security associations on behalf of the kernel. Such security associations can occur as a result of a process having requested some security level through setsockopt(2), or as a result of dynamic VPN entries. Supported values are hmac-md5, hmac-sha1, and hmac-ripemd160. If set to any other value, it is left to the key management daemons to select an authentication algorithm for the security association. The default value is hmac-sha1.

ip.ipsec-bytes

The number of bytes that will be processed by a security association before it expires. If set to less than or equal to zero, the security association will not expire because of this counter. The default value is 0.

ip.ipsec-comp-alg

The compression algorithm to use with an IP Compression Association (IPCA). Possible values are “deflate” and “lzs”. Note that lzs is only available with hifn(4). See ipsecctl(8) for more information.

ip.ipsec-enc-alg

This is the default encryption algorithm the kernel will instruct key management daemons to negotiate when establishing security associations on behalf of the kernel. Such security associations can occur as a result of a process having requested some security level through setsockopt(2), or as a result of dynamic VPN entries. Supported values are aes, des, 3des, blowfish, cast128, and skipjack. If set to any other value, it is left to the key management daemons to select an encryption algorithm for the security association. The default value is aes.

ip.ipsec-expire-acquire

How long the kernel should allow key management to dynamically acquire security associations before re-sending a request. The default value is 30 seconds.

ip.ipsec-firstuse

The number of seconds after a security association is first used before it expires. If set to less than or equal to zero, the security association will not expire because of this timer. The default value is 7200 seconds.

ip.ipsec-invalid-life

The lifetime of embryonic Security Associations (SAs that key management daemons have reserved but not fully established yet) in seconds. If set to less than or equal to zero, embryonic SAs will not expire. The default value is 60.

ip.ipsec-pfs

If set to any non-zero value, the kernel will ask the key management daemons to use Perfect Forward Secrecy when establishing IPsec Security Associations. Perfect Forward Secrecy makes IPsec Security Associations cryptographically distinct from each other, such that breaking the key for one such SA does not compromise any others. Requiring PFS for every security association significantly increases the computational load of isakmpd(8) exchanges. The default value is 1.

ip.ipsec-soft-allocs

The number of IPsec flows that can use a security association before a message is sent by the kernel to key management for renegotiation of the security association. If set to less than or equal to zero, no message is sent to key management. The default value is 0.

ip.ipsec-soft-bytes

The number of bytes that will be processed by a security association before a message is sent by the kernel to key management for renegotiation of the security association. If set to less than or equal to zero, no message is sent to key management. The default value is 0.

ip.ipsec-soft-firstuse

The number of seconds after a security association is first used before a message is sent by the kernel to key management for renegotiation of the security association. If set to less than or equal to zero, no message is sent to key management. The default value is 3600 seconds.

ip.ipsec-soft-timeout

The number of seconds after a security association is established before a message is sent by the kernel to key management for renegotiation of the security association. If set to less than or equal to zero, no message is sent to key management. The default value is 80000 seconds.

ip.ipsec-timeout

The number of seconds after a security association is established before it will expire. If set to less than or equal to zero, the security association will not expire because of this timer. The default value is 86400 seconds.

ip.maxqueue

Fragment flood protection. Sets the maximum number of unassembled IP fragments in the fragment queue.

ip.mforwarding

If set to 1, then multicast forwarding is enabled for the host. The default is 0.

ip.mtudisc

Returns 1 if Path MTU Discovery is enabled.

ip.mtudisctimeout

Returns the number of seconds in which a route added by the Path MTU Discovery engine will time out. When the route times out, the Path MTU Discovery engine will attempt to probe a larger path MTU.

ip.multipath

This variable enables multipath routing for IPv4 addresses. If set to 0, only the first route selected will be used for a given destination regardless of how many routes exist in the routing table.

ip.portfirst

Minimum registered port number for TCP/UDP port allocation. Registered ports can be used by ordinary user processes or programs executed by ordinary users. Cannot be less than 1024 or greater than 49151. Must be less than ip.portlast.

ip.porthifirst

Minimum dynamic/private port number for TCP/UDP port allocation. Dynamic/private ports can be used by ordinary user processes or programs executed by ordinary users. Cannot be less than 49152 or greater than 65535. Must be less than ip.porthilast.

ip.porthilast

Maximum dynamic/private port number for TCP/UDP port allocation. Dynamic/private ports can be used by ordinary user processes or programs executed by ordinary users. Cannot be less than 49152 or greater than 65535. Must be greater than ip.porthifirst.

ip.portlast

Maximum registered port number for TCP/UDP port allocation. Registered ports can be used by ordinary user processes or programs executed by ordinary users. Cannot be less than 1024 or greater than 49151. Must be greater than ip.portfirst.

ip.redirect

Returns 1 when ICMP redirects may be sent by the host. This option is ignored unless the host is routing IP packets, and should normally be enabled on all systems.

ip.sourceroute

Returns 1 when forwarding of source-routed packets is enabled for the host. As detailed in securelevel(7), this variable may not be changed if the securelevel is \*(Gt 0.

ip.stats

Returns the IP statistics in a struct ipstat.

ip.ttl

The maximum time-to-live (hop count) value for an IP packet sourced by the system. This value applies to normal transport protocols, not to ICMP.

ipcomp.enable

Enable the IPComp protocol. See ipsecctl(8) for more information.

ipip.allow

If set to 0, incoming IP-in-IP packets will not be processed. If set to any other value, processing will occur; furthermore, if set to 2, no checks for spoofing of loopback addresses will be done. This is useful only for debugging purposes, and should never be used in production systems.

mobileip.allow

If set to 0, incoming MobileIP encapsulated packets (RFC 2004) will not be processed. If set to any other value, processing will occur.

tcp.ackonpush

Returns 1 if TCP segments with the TH_PUSH flag set are being acknowledged immediately, otherwise 0.

tcp.baddynamic

An array of in_port_t is returned specifying the bitmask of TCP ports between 512 and 1023 inclusive that should not be allocated dynamically by the kernel (i.e., they must be bound specifically by port number).

tcp.ecn

Returns 1 if Explicit Congestion Notifications for TCP are enabled.

tcp.ident

A struct tcp_ident_mapping specifying a local and foreign endpoint of a TCP socket is filled in with the effective and real UIDs of the process that owns the socket. If no such socket exists, then the effective and real UID values are both set to \-1.

tcp.keepidle

If the socket option SO_KEEPALIVE has been set on a socket, then this value specifies how much time a connection needs to be idle before keepalives are sent. See also tcp.slowhz.

tcp.keepinittime

Time to keep alive the initial SYN packet of a TCP handshake.

tcp.keepintvl

Time after a keepalive probe is sent until, in the absence of any response, another probe is sent. See also tcp.slowhz.

tcp.mssdflt

The maximum segment size that is used as default for non-local connections. The default value is 512.

tcp.reasslimit

The maximum number of out-of-order TCP segments the system will store for reassembly.

tcp.recvspace

Returns the default TCP receive buffer size.

tcp.rfc1323

Returns 1 if RFC 1323 extensions to TCP are enabled.

tcp.rfc3390

Returns 1 if the TCP Initial Window is increased, as specified in RFC 3390.

tcp.rstppslimit

This variable specifies the maximum number of outgoing TCP RST packets per second. TCP RST packets exceeding this value are subject to rate limitation and will not go out from the node. A negative value disables rate limitation.

tcp.sack

Returns 1 if RFC 2018 Selective Acknowledgements are enabled.

tcp.sendspace

Returns the default TCP send buffer size.

tcp.slowhz

The units for tcp.keepidle and tcp.keepintvl; those variables are in ticks of a clock that ticks tcp.slowhz times per second. (That is, their values must be divided by the tcp.slowhz value to get times in seconds.)

tcp.stats

Returns the TCP statistics in a struct tcpstat.

tcp.synbucketlimit

The maximum number of entries allowed per hash bucket in the TCP SYN cache.

tcp.syncachelimit

The maximum number of entries allowed in the TCP SYN cache.

udp.baddynamic

Analogous to tcp.baddynamic but for UDP sockets.

udp.checksum

Returns 1 when UDP checksums are being computed and checked. Disabling UDP checksums is strongly discouraged.

udp.recvspace

Returns the default UDP receive buffer size.

udp.sendspace

Returns the default UDP send buffer size.

udp.stats

Returns the UDP statistics in a struct udpstat.

PF_INET6

Get or set various global information about IPv6 (Internet Protocol version 6). The third level name is the protocol. The fourth level name is the variable name. The currently defined protocols and names are:

Protocol name	Variable name	Type	Changeable
icmp6	errppslimit	integer	yes
icmp6	mtudisc_hiwat	integer	yes
icmp6	mtudisc_lowat	integer	yes
icmp6	nd6_debug	integer	yes
icmp6	nd6_delay	integer	yes
icmp6	nd6_maxnudhint	integer	yes
icmp6	nd6_mmaxtries	integer	yes
icmp6	nd6_prune	integer	yes
icmp6	nd6_umaxtries	integer	yes
icmp6	nd6_useloopback	integer	yes
icmp6	nodeinfo	integer	yes
icmp6	rediraccept	integer	yes
icmp6	redirtimeout	integer	yes
ip6	accept_rtadv	integer	yes
ip6	auto_flowlabel	integer	yes
ip6	dad_count	integer	yes
ip6	defmcasthlim	integer	yes
ip6	forwarding	integer	yes
ip6	hdrnestlimit	integer	yes
ip6	hlim	integer	yes
ip6	kame_version	string	no
ip6	keepfaith	integer	yes
ip6	log_interval	integer	yes
ip6	maxfragpackets	integer	yes
ip6	maxfrags	integer	yes
ip6	mforwarding	integer	yes
ip6	multicast_mtudisc	integer	yes
ip6	multipath	integer	yes
ip6	redirect	integer	yes
ip6	rr_prune	integer	yes
ip6	use_deprecated	integer	yes
ip6	v6only	integer	no

The variables are as follows:

icmp6.errppslimit

This variable specifies the maximum number of outgoing ICMPv6 error messages per second. ICMPv6 error messages exceeding this value are subject to rate limitation and will not go out from the node. A negative value will disable the rate limitation.

icmp6.mtudisc_hiwat

icmp6.mtudisc_lowat

These variables define the maximum number of routing table entries created due to path MTU discovery (preventing denial-of-service attacks with ICMPv6 too big messages). After IPv6 path MTU discovery happens, path MTU information is kept in the routing table. If the number of routing table entries exceeds this value, the kernel will not attempt to keep the path MTU information. icmp6.mtudisc_hiwat is used when we have verified ICMPv6 too big messages. icmp6.mtudisc_lowat is used when we have unverified ICMPv6 too big messages. Verification is performed by using address/port pairs kept in connected PCBs. A negative value disables the upper limit.

icmp6.nd6_debug

If set to non-zero, IPv6 neighbor discovery will generate debugging messages. The debug output is useful for diagnosing IPv6 interoperability issues. The flag must be set to 0 for normal operation.

icmp6.nd6_delay

This variable specifies the DELAY_FIRST_PROBE_TIME timing constant in IPv6 neighbor discovery specification (RFC 2461), in seconds.

icmp6.nd6_maxnudhint

IPv6 neighbor discovery permits upper layer protocols to supply reachability hints, to avoid unnecessary neighbor discovery exchanges. This variable defines the number of consecutive hints the neighbor discovery layer will take. For example, by setting the variable to 3, neighbor discovery will take a maximum of 3 consecutive hints. After receiving 3 hints, the neighbor discovery layer will instead perform the normal neighbor discovery process.

icmp6.nd6_mmaxtries

This variable specifies the MAX_MULTICAST_SOLICIT constant in IPv6 neighbor discovery specification (RFC 2461).

icmp6.nd6_prune

This variable specifies the interval between IPv6 neighbor cache babysitting in seconds.

icmp6.nd6_umaxtries

This variable specifies the MAX_UNICAST_SOLICIT constant in IPv6 neighbor discovery specification (RFC 2461).

icmp6.nd6_useloopback

If set to non-zero, IPv6 will use the loopback interface for local traffic.

icmp6.nodeinfo

This variable enables responses to ICMPv6 node information queries. If set to 0, responses will not be generated for ICMPv6 node information queries. Since node information queries can have a security impact, it is possible to fine tune which responses should be answered. Two separate bits can be set:

1

Respond to ICMPv6 FQDN queries, e.g.\& ping6 -w.

2

Respond to ICMPv6 node addresses queries, e.g.\& ping6 -a.

icmp6.rediraccept

If set to non-zero, the host will accept ICMPv6 redirect packets. Note that IPv6 routers will never accept ICMPv6 redirect packets, so the variable is only meaningful on IPv6 hosts, not on routers.

icmp6.redirtimeout

The variable specifies the lifetime of routing entries generated by incoming ICMPv6 redirects.

ip6.accept_rtadv

If set to non-zero, the node will accept ICMPv6 router advertisement packets and autoconfigures address prefixes and default routers. The node must be a host (not a router) for the option to be meaningful (see ip6.forwarding).

ip6.auto_flowlabel

On connected transport protocol packets, fill the IPv6 flowlabel field to help intermediate routers identify packet flows.

ip6.dad_count

This variable configures the number of IPv6 DAD (duplicated address detection) probe packets. These packets are generated when IPv6 interfaces are first brought up.

ip6.defmcasthlim

The default hop limit value for an IPv6 multicast packet sourced by the node. This value applies to all the transport protocols on top of IPv6. Methods for overriding this value are documented in ip6(4).

ip6.forwarding

Returns 1 when IPv6 forwarding is enabled for the node, meaning that the node is acting as a router. Returns 0 when IPv6 forwarding is disabled for the node, meaning that the node is acting as a host. Note that IPv6 defines node behavior for the “router” and “host” cases quite differently, and changing this variable during operation may cause serious trouble. Hence, this variable should only be set at bootstrap time.

ip6.hdrnestlimit

The number of IPv6 extension headers permitted on incoming IPv6 packets. If set to 0, the node will accept as many extension headers as possible.

ip6.hlim

The default hop limit value for an IPv6 unicast packet sourced by the node. This value applies to all the transport protocols on top of IPv6. Methods for overriding this value are documented in ip6(4).

ip6.kame_version

This string identifies the version of the KAME IPv6 stack implemented in the kernel.

ip6.keepfaith

If set to non-zero, enables the “FAITH” TCP relay IPv6-to-IPv4 translator code in the kernel. Refer to faith(4) and faithd(8) for more details.

ip6.log_interval

This variable permits adjusting the amount of logs generated by the IPv6 packet forwarding engine. The value indicates the number of seconds of interval which must elapse between log output.

ip6.maxfragpackets

The maximum number of fragmented packets the node will accept. 0 means that the node will not accept any fragmented packets. \-1 means that the node will accept as many fragmented packets as it receives. The flag is provided basically for avoiding possible DoS attacks.

ip6.maxfrags

The maximum number of fragments the node will accept. 0 means that the node will not accept any fragments. \-1 means that the node will accept as many fragments as it receives. The flag is provided basically for avoiding possible DoS attacks.

ip6.mforwarding

If set to 1, then multicast forwarding is enabled for the host. The default is 0.

ip6.multicast_mtudisc

This variable controls generation of ICMPv6 Too Big messages when the machine is performing as an IPv6 multicast router. If set to 1, an ICMPv6 Too Big message will be generated for multicast packets which were too big to be forwarded. If set to 0, the ICMPv6 Too Big message will be suppressed.

ip6.multipath

This variable enables multipath routing for IPv6 addresses. If set to 0, only the first route selected will be used for a given destination regardless of how many routes exist in the routing table.

ip6.redirect

Returns 1 when ICMPv6 redirects may be sent by the node. This option is ignored unless the node is routing IP packets, and should normally be enabled on all systems.

ip6.rr_prune

This variable specifies the interval between IPv6 router renumbering prefix babysitting in seconds.

ip6.use_deprecated

This variable controls the use of deprecated addresses, specified in RFC 2462 5.5.4.

ip6.v6only

The variable specifies the initial value for the IPV6_V6ONLY socket option for an AF_INET6 socket. It is always 1 for OpenBSD.

We reuse net.inet.tcp and net.inet.udp for TCP/UDP over IPv6.

CTL_USER

USER_BC_BASE_MAX

The maximum ibase/obase values in the bc(1) utility.

USER_BC_DIM_MAX

The maximum array size in the bc(1) utility.

USER_BC_SCALE_MAX

The maximum scale value in the bc(1) utility.

USER_BC_STRING_MAX

The maximum string length in the bc(1) utility.

USER_COLL_WEIGHTS_MAX

The maximum number of weights that can be assigned to any entry of the LC_COLLATE order keyword in the locale definition file.

USER_CS_PATH

Return a value for the PATH environment variable that finds all the standard utilities.

USER_EXPR_NEST_MAX

The maximum number of expressions that can be nested within parentheses by the expr(1) utility.

USER_LINE_MAX

The maximum length in bytes of a text-processing utility's input line.

USER_POSIX2_C_BIND

Return 1 if the system's C-language development facilities support the C-Language Bindings Option, otherwise 0.

USER_POSIX2_C_DEV

Return 1 if the system supports the C-Language Development Utilities Option, otherwise 0.

USER_POSIX2_CHAR_TERM

Return 1 if the system supports at least one terminal type capable of all operations described in POSIX 1003.2, otherwise 0.

USER_POSIX2_FORT_DEV

Return 1 if the system supports the FORTRAN Development Utilities Option, otherwise 0.

USER_POSIX2_FORT_RUN

Return 1 if the system supports the FORTRAN Runtime Utilities Option, otherwise 0.

USER_POSIX2_LOCALEDEF

Return 1 if the system supports the creation of locales, otherwise 0.

USER_POSIX2_SW_DEV

Return 1 if the system supports the Software Development Utilities Option, otherwise 0.

USER_POSIX2_UPE

Return 1 if the system supports the User Portability Utilities Option, otherwise 0.

USER_POSIX2_VERSION

The version of POSIX 1003.2 with which the system attempts to comply.

USER_RE_DUP_MAX

The maximum number of repeated occurrences of a regular expression permitted when using interval notation.

USER_STREAM_MAX

The maximum number of streams that a process may have open at any one time.

USER_TZNAME_MAX

The minimum maximum number of types supported for the name of a time zone.

CTL_VFS

VFS_GENERIC

This second level identifier requests generic information about the VFS layer. Within it, the following third level identifiers exist:

Third level name	Type	Changeable
VFS_CONF	struct vfsconf	no
VFS_MAXTYPENUM	int	no

filesystem #

After finding the filesystem dependent vfc_typenum using VFS_GENERIC with VFS_CONF, it is possible to access filesystem dependent information.

Some filesystems may contain settings.

FFS

Third level name	Type	Changeable
FFS_ASYNCFREE	integer	yes
FFS_CLUSTERREAD	integer	yes
FFS_CLUSTERWRITE	integer	yes
FFS_DIRHASH_DIRSIZE	integer	yes
FFS_DIRHASH_MAXMEM	integer	yes
FFS_DIRHASH_MEM	integer	no
FFS_MAXSOFTDEPS	integer	yes
FFS_REALLOCBLOCKS	integer	yes
FFS_SD_BLK_LIMIT_HIT	integer	yes
FFS_SD_BLK_LIMIT_PUSH	integer	yes
FFS_SD_DIR_ENTRY	integer	yes
FFS_SD_DIRECT_BLK_PTRS	integer	yes
FFS_SD_INDR_BLK_PTRS	integer	yes
FFS_SD_INO_LIMIT_HIT	integer	yes
FFS_SD_INO_LIMIT_PUSH	integer	yes
FFS_SD_INODE_BITMAP	integer	yes
FFS_SD_SYNC_LIMIT_HIT	integer	yes
FFS_SD_TICKDELAY	integer	yes
FFS_SD_WORKLIST_PUSH	integer	yes

FFS_CLUSTERREAD

Enable combining multiple reads into one request to improve performance.

FFS_CLUSTERWRITE

Enable combining multiple writes into one request.

FFS_DIRHASH_DIRSIZE

The minimum size of a directory, in bytes, before it is considered for hashing.

FFS_DIRHASH_MAXMEM

The maximum amount of memory, in bytes, to be used for storing directory hashes.

FFS_DIRHASH_MEM

The amount of memory currently used by all directory hashes.

FFS_REALLOCBLOCKS

When enabled, the kernel will attempt to relocate growing files so that they are contiguous on disk, reducing fragmentation.

NFS

Third level name	Type	Changeable
NFS_NFSSTATS	struct nfsstats	yes
NFS_NIOTHREADS	int	yes

NFS_NIOTHREADS

The number of NFS I/O kernel threads. Should be set high enough for the server to handle the maximum level of concurrency from its clients, typically four to six.

CTL_VM

VM_ANONMIN

Percentage of physical memory available for pages which contain anonymous mapping.

VM_LOADAVG

Return the load average history. The returned data consists of a struct loadavg.

VM_MAXSLP

The time for a process to be blocked before being swappable, in seconds.

VM_METER

Return the system wide virtual memory statistics. The returned data consists of a struct vmtotal.

VM_NKMEMPAGES

Number of pages in kmem_map.

VM_PSSTRINGS

Returns the address of the process struct ps_strings. The ps(1) program uses it to locate the argument and environment strings.

VM_SWAPENCRYPT

Contains statistics about swap encryption. The string and integer information available for the third level is detailed below.

Third level name	Type	Changeable
SWPENC_CREATED	integer	no
SWPENC_DELETED	integer	no
SWPENC_ENABLE	integer	yes

SWPENC_CREATED

The number of encryption keys that have been randomly created. The swap partition is divided into sections of normally 512KB. Each section has its own encryption key.

SWPENC_DELETED

The number of encryption keys that have been deleted, thus effectively erasing the data that has been encrypted with them. Encryption keys are deleted when their reference counter reaches zero.

SWPENC_ENABLE

Set to 1 to enable swap encryption for all processes. A 0 disables swap encryption. Pages still on swap receive a grandfather clause. Turning this option on does not affect legacy swap data already on the disk, but all newly written data will be encrypted. When swap encryption is turned on, automatic crash(8) dumps are disabled.

VM_USPACE

The number of bytes allocated for each kernel stack.

VM_UVMEXP

Contains statistics about the UVM memory management system.

VM_VNODEMIN

Percentage of physical memory available for pages which contain cached file data.

VM_VTEXTMIN

Percentage of physical memory available for pages which contain cached executable data.

RETURN VALUES

FILES

‹sys/sysctl.h›

definitions for top level identifiers, second level kernel and hardware identifiers, and user level identifiers

‹sys/socket.h›

definitions for second level network identifiers

‹sys/gmon.h›

definitions for third level profiling identifiers

‹ufs/ffs/ffs_extern.h›

definitions for third level virtual file system identifiers (ffs)

‹nfs/nfs.h›

definitions for third level virtual file system identifiers (nfs)

‹uvm/uvm_param.h›

definitions for second level virtual memory identifiers

‹uvm/uvm_swap_encrypt.h›

definitions for third level virtual memory identifiers

‹netinet/in.h›

definitions for third level IPv4/v6 identifiers and fourth level IP and IPv6 identifiers

‹netinet/icmp_var.h›

definitions for fourth level ICMP identifiers

‹netinet/icmp6.h›

definitions for fourth level ICMPv6 identifiers

‹netinet/tcp_var.h›

definitions for fourth level TCP identifiers

‹netinet/udp_var.h›

definitions for fourth level UDP identifiers

‹machine/cpu.h›

definitions for second level CPU identifiers

ERRORS

[EFAULT]

The buffer name, oldp, newp, or length pointer oldlenp contains an invalid address.

[EINVAL]

The name array is less than two or greater than CTL_MAXNAME.

[EINVAL]

A non-null newp pointer is given and its specified length in newlen is too large or too small.

[ENOMEM]

The length pointed to by oldlenp is too short to hold the requested value.

[ENOTDIR]

The name array specifies an intermediate rather than terminal name.

[EOPNOTSUPP]

The name array specifies a value that is unknown.

[EPERM]

An attempt is made to set a read-only value.

[EPERM]

A process without appropriate privileges attempts to set a value.

[EPERM]

An attempt to change a value protected by the current kernel security level is made.

[ESRCH]

No process could be found which corresponds to the given process ID.

SEE ALSO

HISTORY