OPTIONS(4)                NetBSD Programmer's Manual                OPTIONS(4)

NAME
     options - Miscellaneous kernel configuration options

SYNOPSIS
     options ...

DESCRIPTION
     This manual page describes a number of miscellaneous kernel configuration
     options that may be specified in a kernel config file.  See config(8) for
     information on how to configure and build kernels.  Note: Options are
     passed to the compile process as -D flags to the C compiler.

   Compatibility Options

     options COMPAT_09
     Enable binary compatibility with NetBSD 0.9.  This enables support for
     16-bit user, group, and process ids (following revisions support 32-bit
     identifiers), It also allows the use of the deprecated getdomainname(3),
     setdomainname(3), and uname(3) syscalls.  This option also allows using
     numeric filesystem identifiers rather than strings.  Post NetBSD 0.9 ver-
     sions use string identifiers.

     options COMPAT_10
     Enable binary compatibility with NetBSD 1.0.  This option allows the use
     of the filesystem name of ``ufs'' as an alias for ``ffs''.  The name
     ``ffs'' should be used post 1.0 in /etc/fstab and other files.  It also
     adds old syscalls for the AT&T System V UNIX shared memory interface.
     This was changed post 1.0 to work on 64-bit architectures.  This option
     also enables ``sgtty'' compatibility, without which programs using the
     old interface produce an ``inappropriate ioctl'' error, and /dev/io only
     works when this option is set in the kernel, see io(4) on ports that sup-
     port it.

     options COMPAT_11
     Enable binary compatibility with NetBSD 1.1.  This allows binaries run-
     ning on the i386 port to gain direct access to the io ports by opening
     /dev/io read/write.  This functionality was replaced by i386_iopl(2) post
     1.1.  On the Atari port, the location of the disk label was moved after
     1.1.  When the COMPAT_11 option is set, the kernel will read (pre) 1.1
     style disk labels as a last resort.  When a disklabel is re-written, the
     old style label will be replaced with a post 1.1 style label.  This also
     enables EXEC_ELF_NOTELESS option.

     options COMPAT_12
     Enable binary compatibility with NetBSD 1.2.  This allows the use of old
     syscalls for reboot() and swapon().  The syscall numbers were changed
     post 1.2 to add functionality to the reboot(2) syscall, and the new
     swapctl(2) interface was introduced.  This also enables EXEC_ELF_NOTELESS
     option.

     options COMPAT_13
     Enable binary compatibility with NetBSD 1.3.  This allows the use of old
     syscalls for sigaltstack(), and also enables the old swapctl(2) command
     SWAP_STATS (now called SWAP_OSTATS), which does not include the se_path
     member of struct swapent.

     options COMPAT_14
     Enable binary compatibility with NetBSD 1.4.  This allows some old
     ioctl(2) on wscons(4) to be performed, and allows the NFSSVC_BIOD mode of
     the nfssvc(2) system call to be used for compatibility with the deprecat-
     ed nfsiod program.

     options COMPAT_43
     Enables compatibility with 4.3BSD.  This adds an old syscall for
     lseek(2).  It also adds the ioctls for TIOCGETP and TIOCSETP.  The return
     values for getpid(2), getgid(2), and getuid(2) syscalls are modified as
     well, to return the parent's pid and uid as well as the current pro-
     cess's.  It also enables the deprecated NTTYDISC terminal line disci-
     pline.  It also provides backwards compatibility with ``old''
     SIOC[GS]IF{ADDR,DSTADDR,BRDADDR,NETMASK} interface ioctls, including bi-
     nary compatibility with code written before the introduction of the
     sa_len field in sockaddrs.  It also enables support for some older pre
     4.4BSD socket calls.

     options COMPAT_SVR4
     On those architectures that support it, this enables binary compatibility
     with AT&T System V.4 UNIX applications built for the same architecture.
     This currently includes the i386, m68k and sparc port.

     options COMPAT_LINUX
     On those architectures that support it, this enables binary compatibility
     with Linux ELF and a.out(5) applications built for the same architecture.
     This currently includes the alpha, i386, powerpc, and m68k ports. There
     is also a minimal support for running Linux binaries on Mips ports, but
     it is experimental at the moment.

     options COMPAT_SUNOS
     On those architectures that support it, this enables binary compatibility
     with SunOS 4.1 applications built for the same architecture.  This cur-
     rently includes the sparc, sparc64 and most or all m68k ports.  Note that
     the sparc64 requires the COMPAT_NETBSD32 option for 64-bit kernels, in
     addition to this option.

     options COMPAT_ULTRIX
     On those architectures that support it, this enables binary compatibility
     with Ultrix applications built for the same architecture.  This currently
     is limited to the pmax.  The functionality of this option is unknown.

     options COMPAT_FREEBSD
     On those architectures that support it, this enables binary compatibility
     with FreeBSD applications built for the same architecture.  At the moment
     this is limited to the i386 port.

     options COMPAT_HPUX
     On those architectures that support it, this enables binary compatibility
     with HP/UX applications built for the same architecture.  This is limited
     to the hp300 port, and has some known bugs.  A limited set of programs do
     work.

     options COMPAT_IBCS2
     On those architectures that support it, this enables binary compatibility
     with iBCS2 or SVR3 applications built for the same architecture.  This is
     currently limited to the i386 and vax ports.

     options COMPAT_IRIX
     On those architectures that support it, this enables binary compatibility
     with IRIX o32 binaries built for the same architecture.  This feature is
     experimental, and it is currently limited to the sgimips port of NetBSD.

     options COMPAT_OSF1
     On those architectures that support it, this enables binary compatibility
     with Digital UNIX (formerly OSF/1) applications built for the same archi-
     tecture.  This is currently limited to the alpha port.

     options COMPAT_NOMID
     Enable compatibility with a.out(5) executables that lack a machine ID.
     This includes NetBSD 0.8's ZMAGIC format, and 386BSD and BSDI's QMAGIC,
     NMAGIC, and OMAGIC a.out(5) formats.

     options COMPAT_NETBSD32
     On those architectures that support it, this enables binary compatibility
     with 32-bit applications built for the same architecture.  This is cur-
     rently limited to the sparc64 port, and only applicable for 64-bit ker-
     nels.

     options COMPAT_SVR4_32
     On those architectures that support it, this enables binary compatibility
     with 32-bit SVR4 applications built for the same architecture.  This is
     currently limited to the sparc64 port, and only applicable for 64-bit
     kernels.

     options COMPAT_AOUT_M68K
     On m68k architectures which have switched to ELF, this enable binary com-
     patibility with NetBSD/m68k a.out(5) executables on NetBSD/m68k ELF ker-
     nel.  This handles alignment incompatibility of m68k ABI between a.out
     and ELF which causes the structure padding differences.  Currently only
     some system calls which use struct stat are adjusted and some binaries
     which use sysctl(3) to retrieve network details would not work properly.

     options EXEC_ELF_NOTELESS
     Run unidentified ELF binaries as NetBSD binaries.  This might be needed
     for very old NetBSD ELF binaries on some archs.  These old binaries
     didn't contain an appropriate .note.netbsd.ident section, and thus can't
     be identified by the kernel as NetBSD binaries otherwise.  Beware - if
     this option is on, the kernel would run any unknown ELF binaries as if
     they were NetBSD binaries.

   Debugging Options

     options DDB
     Compiles in a kernel debugger for diagnosing kernel problems.  See ddb(4)
     for details.  NOTE: not available on all architectures.

     options DDB_FROMCONSOLE=integer
     If set to non-zero, DDB may be entered by sending a break on a serial
     console or by a special key sequence on a graphics console.  A value of
     "0" ignores console breaks or key sequences, It not explicitly specified,
     the default value is "1".  Note that this sets the value of the
     ddb.fromconsole sysctl(3) variable which may be changed at run time --
     see sysctl(8) for details.

     options DDB_HISTORY_SIZE=integer
     If this is non-zero, enable history editing in the kernel debugger and
     set the size of the history to this value.

     options DDB_ONPANIC
     If set to non-zero, DDB will be entered upon kernel panic.  The default
     if not specified is "1".  Note that this sets the value of the
     ddb.onpanic sysctl(3) variable which may be changed at run time -- see
     sysctl(8) for details.

     options DDB_BREAK_CHAR=integer
     This option overrides the using break to enter the kernel debugger on the
     serial console.  The value given will is the ascii value to be used in-
     stead.  This is currently only supported by the com driver.

     options KGDB
     Compiles in a remote kernel debugger stub for diagnosing kernel problems
     using the ``remote target'' feature of gdb.  See gdb(1) for details.
     NOTE: not available on all architectures.

     options KGDB_DEV
     Device number (as a dev_t) of kgdb device.

     options KGDB_DEVADDR
     Memory address of kgdb device.

     options KGDB_DEVMODE
     Permissions of kgdb device.

     options KGDB_DEVNAME
     Device name of kgdb device.

     options KGDB_DEVRATE
     Baud rate of kgdb device.

     makeoptions DEBUG="-g"
     The -g flag causes netbsd.gdb to be built in addition to netbsd.
     netbsd.gdb is useful for debugging kernel crash dumps with gdb.  The com-
     mand
           gdb -k
     invokes gdb in kernel debugger mode.  See gdb(1) for details.  This also
     turns on options DEBUG (which see).

     options DEBUG
     Turns on miscellaneous kernel debugging.  Since options are turned into
     preprocessor defines (see above), options DEBUG is equivalent to doing a
     #define DEBUG throughout the kernel.  Much of the kernel has #ifdef DEBUG
     conditionalized debugging code.  Note that many parts of the kernel (typ-
     ically device drivers) include their own #ifdef XXX_DEBUG conditionals
     instead.  This option also turns on certain other options, which may de-
     crease system performance.

     options DIAGNOSTIC
     Adds code to the kernel that does internal consistency checks.  This code
     will cause the kernel to panic if corruption of internal data structures
     is detected. These checks can decrease performance up to 15%.

     options KTRACE
     Add hooks for the system call tracing facility, which allows users to
     watch the system call invocation behavior of processes.  See ktrace(1)
     for details.

     options MSGBUFSIZE=integer
     This option sets the size of the kernel message buffer.  This buffer
     holds the kernel output of printf() when not (yet) read by syslogd(8).
     This is particularly useful when the system has crashed and you wish to
     lookup the kernel output from just before the crash.  Also, since the au-
     toconfig output becomes more and more verbose, it sometimes happens that
     the message buffer overflows before syslogd(8) was able to read it.  Note
     that not all systems are capable of obtaining a variable sized message
     buffer.  There are also some systems on which memory contents are not
     preserved across reboots.

     options MALLOCLOG
     Enables an event log for malloc(9).  Useful for tracking down ``Data
     modified on freelist'' and ``multiple free'' problems.

     options MALLOCLOGSIZE=integer
     Defines the number of entries in the malloc log.  Default is 100000 en-
     tries.

     options UVMHIST
     Enables the UVM history logs, which create in-memory traces of various
     UVM activities. These logs can be displayed be calling uvmhist_dump() or
     uvm_hist() with appropriate arguments from DDB.  See the kernel source
     file sys/uvm/uvm_stat.c for details.

     options UVMHIST_PRINT
     Prints the UVM history logs on the system console as entries are added.
     Note that the output is extremely voluminous, so this option is really
     only useful for debugging the very earliest parts of kernel initializa-
     tion.

   File Systems

     file-system FFS
     Includes code implementing the Berkeley Fast File System (FFS).  Most ma-
     chines need this if they are not running diskless.

     file-system EXT2FS
     Includes code implementing the Second Extended File System (EXT2FS) , re-
     vision 0 and revision 1 with the filetype and sparse_super options.  This
     is the most commonly used file system on the Linux operating system, and
     is provided here for compatibility.  Some of the specific features of
     EXT2FS like the "behavior on errors" are not implemented.  This file sys-
     tem can't be used with UID or GID greater than 65535.  See
     mount_ext2fs(8) for details.

     file-system LFS
     [EXPERIMENTAL] Include the Log-structured File System (LFS).  See
     mount_lfs(8) and newfs_lfs(8) for details.

     file-system MFS
     Include the Memory File System (MFS).  This file system stores files in
     swappable memory, and produces notable performance improvements when it
     is used as the file store for /tmp and similar file systems.  See
     mount_mfs(8) for details.

     file-system NFS
     Include the client side of the Network File System (NFS) remote file
     sharing protocol.  Although the bulk of the code implementing NFS is ker-
     nel based, several user level daemons are needed for it to work.  See
     mount_nfs(8) for details.

     file-system CD9660
     Includes code for the ISO 9660 + Rock Ridge file system, which is the
     standard file system on many CD-ROM discs.  Useful primarily if you have
     a CD-ROM drive.  See mount_cd9660(8) for details.

     file-system MSDOSFS
     Includes the MS-DOS FAT file system, which is reportedly still used by
     unfortunate people who have not heard about NetBSD.  Also implements the
     Windows 95 extensions to the same, which permit the use of longer, mixed
     case file names.  See mount_msdos(8) and fsck_msdos(8) for details.

     file-system NTFS
     [EXPERIMENTAL] Includes code for the Microsoft Windows NT file system.
     See mount_ntfs(8) for details.

     file-system FDESC
     Includes code for a file system, conventionally mounted on /dev/fd, which
     permits access to the per-process file descriptor space via special files
     in the file system.  See mount_fdesc(8) for details.  Note that this fa-
     cility is redundant, and thus unneeded on most NetBSD systems, since the
     fd(4) pseudodevice driver already provides identical functionality.  On
     most NetBSD systems, instances of fd(4) are mknoded under /dev/fd/ and on
     /dev/stdin, /dev/stdout, and /dev/stderr.

     file-system KERNFS
     Includes code which permits the mounting of a special file system (nor-
     mally mounted on /kern) in which files representing various kernel vari-
     ables and parameters may be found.  See mount_kernfs(8) for details.

     file-system NULLFS
     Includes code for a loopback file system.  This permits portions of the
     file hierarchy to be re-mounted in other places.  The code really exists
     to provide an example of a stackable file system layer.  See
     mount_null(8) for details.

     file-system OVERLAY
     Includes code for a file system filter.  This permits the overlay file
     system to intercept all access to an underlying file system. This file
     system is intended to serve as an example of a stacking file system which
     has a need to interpose itself between an underlying file system and all
     other access.  See mount_overlay(8) for details.

     file-system PORTAL
     [EXPERIMENTAL] Includes the portal filesystem.  This permits interesting
     tricks like opening TCP sockets by opening files in the file system.  The
     portal file system is conventionally mounted on /p and is partially im-
     plemented by a special daemon.  See mount_portal(8) for details.

     file-system PROCFS
     Includes code for a special file system (conventionally mounted on /proc)
     in which the process space becomes visible in the file system.  Among
     other things, the memory spaces of processes running on the system are
     visible as files, and signals may be sent to processes by writing to ctl
     files in the procfs namespace.  See mount_procfs(8) for details.

     file-system UMAPFS
     Includes a loopback file system in which user and group ids may be
     remapped -- this can be useful when mounting alien file systems with dif-
     ferent uids and gids than the local system.  See mount_umap(8) for de-
     tails.

     file-system UNION
     [EXPERIMENTAL] Includes code for the union file system, which permits di-
     rectories to be mounted on top of each other in such a way that both file
     systems remain visible -- this permits tricks like allowing writing (and
     the deleting of files) on a read-only file system like a CD-ROM by mount-
     ing a local writable file system on top of the read-only file system.
     See mount_union(8) for details.

     file-system CODA
     [EXPERIMENTAL] Includes code for the Coda file system.  Coda is a dis-
     tributed file system like NFS and AFS.  It is freely available, like NFS,
     but it functions much like AFS in being a ``stateful'' file system.  Both
     Coda and AFS cache files on your local machine to improve performance.
     Then Coda goes a step further than AFS by letting you access the cached
     files when there is no available network, viz. disconnected laptops and
     network outages.  In Coda, both the client and server are outside the
     kernel which makes them easier to experiment with.  Coda is available for
     several UNIX and non-UNIX platforms.  See http://www.coda.cs.cmu.edu for
     more details.  NOTE: You also need to enable the pseudo-device, vcoda,
     for the Coda filesystem to work.

   File System Options

     options NFSSERVER
     Include the server side of the NFS (Network File System) remote file
     sharing protocol.  Although the bulk of the code implementing NFS is ker-
     nel based, several user level daemons are needed for it to work.  See
     mountd(8) and nfsd(8) for details.

     options QUOTA
     Enables kernel support for file system quotas.  See quotaon(8),
     edquota(8), and quota(1) for details.  Note that quotas only work on
     ``ffs'' file systems, although rpc.rquotad(8) permits them to be accessed
     over NFS.

     options FFS_EI
     Enable ``Endian-Independent'' FFS support.  This allows a system to mount
     an FFS filesystem created for another architecture, at a small perfor-
     mance cost for all FFS filesystems.  See also newfs(8), fsck_ffs(8),
     dumpfs(8) for filesystem byte order status and manipulation.

     options NVNODE=integer
     This option sets the size of the cache used by the name-to-inode transla-
     tion routines, (a.k.a. the namei() cache, though called by many other
     names in the kernel source).  By default, this cache has NPROC (set as 20
     + 16 * MAXUSERS) * (80 + NPROC / 8) entries.  A reasonable way to derive
     a value of NVNODE, should you notice a large number of namei cache misses
     with a tool such as systat(1), is to examine your system's current com-
     puted value with sysctl(8), (which calls this parameter "kern.maxvnodes")
     and to increase this value until either the namei cache hit rate improves
     or it is determined that your system does not benefit substantially from
     an increase in the size of the namei cache.

     options NAMECACHE_ENTER_REVERSE
     Causes the namei cache to always enter a reverse mapping (vnode -> name)
     as well as a normal one. Normally, this is already done for directory vn-
     odes, to speed up the getcwd operation. This option will cause longer
     hash chains in the reverse cache, and thus slow down getcwd somewhat.
     However, it does make vnode -> path translations possible in some cases.
     For now, only useful if strict /proc/#/maps emulation for Linux binaries
     is required.

     options EXT2FS_SYSTEM_FLAGS
     This option changes the behavior of the APPEND and IMMUTABLE flags for a
     file on an EXT2FS filesystem.  Without this option, the superuser or own-
     er of the file can set and clear them.  With this option, only the supe-
     ruser can set them, and they can't be cleared if the securelevel is
     greater than 0.  See also chflags(1).

     options NFS_BOOT_BOOTP
     Enable use of the BOOTP protocol (RFC 951, 1048) to get configuration in-
     formation if NFS is used to mount the root file system.  See diskless(8)
     for details.

     options NFS_BOOT_DHCP
     Same as ``NFS_BOOT_BOOTP'', but use the DHCP extensions to the BOOTP pro-
     tocol (RFC 1541).

     options NFS_BOOT_BOOTP_REQFILE
     Specifies the string sent in the bp_file field of the BOOTP / DHCP re-
     quest packet.

     options NFS_BOOT_BOOTPARAM
     Enable use of the BOOTPARAM protocol, consisting of RARP and BOOTPARAM
     RPC, to get configuration information if NFS is used to mount the root
     file system.  See diskless(8) for details.

     options NFS_BOOT_RWSIZE=value
     Set the initial NFS read and write sizes for diskless-boot requests.  The
     normal default is 8Kbytes.  This option provides a way to lower the value
     (e.g., to 1024 bytes) as a workaround for buggy network interface cards
     or boot proms. Once booted, the read and write request sizes can be in-
     creased by remounting the filesystem. See mount_nfs(8) for details.

     options NFS_V2_ONLY
     Reduce the size of the NFS client code by omitting code that's only re-
     quired for NFSv3 and NQNFS support, leaving only that code required to
     use NFSv2 servers.

   Miscellaneous Options

     options LKM
     Enable loadable kernel modules.  See lkm(4) for details.  NOTE: not
     available on all architectures.

     options INSECURE
     Hardwires the kernel security level at -1.  This means that the system
     always runs in secure level 0 mode, even when running multiuser.  See the
     manual page for init(8) for details on the implications of this.  The
     kernel secure level may manipulated by the superuser by altering the
     kern.securelevel sysctl(3) variable (the secure level may only be lowered
     by a call from process ID 1, i.e.  init(8)).  See also sysctl(8) and
     sysctl(3).

     options UCONSOLE
     Normally, only the superuser can execute the TIOCCONS ioctl(2), which
     redirects console output to a non-console tty.  See tty(4) for details.
     This option permits any user to execute the TIOCCONS ioctl(2).  This is
     useful on machines such as personal workstations which run X(7) servers,
     where one would prefer to permit console output to be viewed in a window
     without requiring a suid root program to do it.

     options MEMORY_DISK_HOOKS
     This option allows for some machine dependent functions to be called when
     the md(4) RAM disk driver is configured.  This can result in automatical-
     ly loading a RAM disk from floppy on open (among other things).

     options MEMORY_DISK_IS_ROOT
     Forces the md(4) RAM disk to be the root device.  This can only be over-
     ridden when the kernel is booted in the 'ask-for-root' mode.

     options MEMORY_DISK_ROOT_SIZE=integer
     Allocates the given number of 512 byte blocks as memory for the md(4) RAM
     disk, to be populated with mdsetimage(8).

     options VNODE_OP_NOINLINE
     Do not inline the VOP_*() calls in the kernel.  On i386 GENERIC, this
     saves 36k of kernel text.  Useful for install media kernels, small memory
     systems and embedded systems.

     options MALLOC_NOINLINE
     Time critical fixed size memory allocation is performed with MALLOC() and
     FREE().  Normally these expand to inline code, but with MALLOC_NOINLINE
     these call the normal malloc() and free() functions.  Useful for install
     media kernels, small memory systems and embedded systems.

     options HZ=integer
     On ports that support it, set the system clock frequency (see hz(9)) to
     the supplied value. Handle with care.

     options NTP
     Turns on in-kernel precision timekeeping support used by software imple-
     menting NTP (Network Time Protocol, RFC1305).  The NTP option adds an in-
     kernel Phase-Locked Loop (PLL) for normal NTP operation, and a Frequency-
     Locked Loop (FLL) for intermittently-connected operation.  ntpd(8) will
     employ a user-level PLL when kernel support is unavailable, but the in-
     kernel version has lower latency and more precision, and so typically
     keeps much better time.  The interface to the kernel NTP support is pro-
     vided by the ntp_adjtime(2) and ntp_gettime(2) system calls, which are
     intended for use by ntpd(8) and are enabled by the option.  On systems
     with sub-microsecond resolution timers, or where (HZ / 100000) is not an
     integer, the NTP option also enables extended-precision arithmetic to
     keep track of fractional clock ticks at NTP time-format precision.

     options PPS_SYNC
     This option enables a kernel serial line discipline for receiving time
     phase signals from an external reference clock such as a radio clock.
     (The NTP option (which see) must be on if the PPS_SYNC option is used.)
     Some reference clocks generate a Pulse Per Second (PPS) signal in phase
     with their time source.  The PPS line discipline receives this signal on
     either the data leads or the DCD control lead of a serial port.  NTP uses
     the PPS signal to discipline the local clock oscillator to a high degree
     of precision (typically less than 50 microseconds in time and 0.1 ppm in
     accuracy).  PPS can also generate a serial output pulse when the system
     receives a PPS interrupt.  This can be used to measure the system inter-
     rupt latency and thus calibrate NTP to account for it.  Using PPS usually
     requires a gadget box to convert from TTL to RS-232 signal levels.  The
     gadget box and PPS are described in more detail in the HTML documentation
     for ntpd(8) in /usr/share/doc/html/ntp.

     options SETUIDSCRIPTS
     Allows scripts with the setuid bit set to execute as the effective user
     rather than the real user, just like binary executables.

     NOTE: Using this option will also enable options FDSCRIPTS

     option FDSCRIPTS
     Allows execution of scripts with the execute bit set, but not the read
     bit, by opening the file and passing the file descriptor to the shell,
     rather than the filename.

     NOTE: Execute only (non-readable) scripts will have argv[0] set to
     /dev/fd/*.  What this option allows as far as security is concerned, is
     the ability to safely ensure that the correct script is run by the inter-
     preter, as it is passed as an already open file.

     options PUCCN
     Enables treating serial ports found on PCI boards puc(4) as potential
     console devices.  The method for choosing such a console device is port
     dependent.

     options RTC_OFFSET=integer
     The kernel (and typically the hardware battery backed-up clock on those
     machines that have one) keeps time in UTC (Universal Coordinated Time,
     once known as GMT, or Greenwich Mean Time) and not in the time of the lo-
     cal time zone.  The RTC_OFFSET option is used on some ports (such as the
     i386) to tell the kernel that the hardware clock is offset from UTC by
     the specified number of minutes.  This is typically used when a machine
     boots several operating systems and one of them wants the hardware clock
     to run in the local time zone and not in UTC, e.g.  RTC_OFFSET=300 means
     the hardware clock is set to US Eastern Time (300 minutes behind UTC),
     and not UTC.  (Note: RTC_OFFSET is used to initialize a kernel variable
     named rtc_offset which is the source actually used to determine the clock
     offset, and which may be accessed via the kern.rtc_offset sysctl vari-
     able.  See sysctl(8) and sysctl(3) for details.  Since the kernel clock
     is initialized from the hardware clock very early in the boot process, it
     is not possible to meaningfully change rtc_offset in system initializa-
     tion scripts.  Changing this value currently may only be done at kernel
     compile time or by patching the kernel and rebooting).

     NOTE: Unfortunately, in many cases where the hardware clock is kept in
     local time, it is adjusted for Daylight Savings Time; this means that at-
     tempting to use RTC_OFFSET to let NetBSD coexist with such an operating
     system, like Windows, would necessitate changing RTC_OFFSET twice a year.
     As such, this solution is imperfect.

     options KMEMSTATS
     The kernel memory allocator, malloc(9), will keep statistics on its per-
     formance if this option is enabled.  Unfortunately, this option therefore
     essentially disables the MALLOC() and FREE() forms of the memory alloca-
     tor, which are used to enhance the performance of certain critical sec-
     tions of code in the kernel.  This option therefore can lead to a signif-
     icant decrease in the performance of certain code in the kernel if en-
     abled.  Examples of such code include the namei() routine, the ccd(4)
     driver, the ncr(4) driver, and much of the networking code.

     options MAXUPRC=integer
     Sets the soft RLIMIT_NPROC resource limit, which specifies the maximum
     number of simultaneous processes a user is permitted to run, for process
     0; this value is inherited by its child processes.  It defaults to
     CHILD_MAX, which is currently defined to be 160.  Setting MAXUPRC to a
     value less than CHILD_MAX is not permitted, as this would result in a vi-
     olation of the semantics of IEEE Std 1003.1-1990 (``POSIX'').

     options DEFCORENAME=string
     Sets the default value of the kern.defcorename sysctl variable, otherwise
     it is set to %n.core.  See sysctl(8) and sysctl(3) for details.

     options RASOPS_CLIPPING
     Enables clipping within the rasops raster-console output system.  NOTE:
     only available on architectures that use rasops for console output.

     options RASOPS_SMALL
     Removes optimized character writing code from the rasops raster-console
     output system.  NOTE: only available on architectures that use rasops for
     console output.

     options INCLUDE_CONFIG_FILE
     Embeds the kernel config file used to define the kernel in the kernel bi-
     nary itself.  The embedded data also includes any files directly included
     by the config file itself, e.g.  GENERIC.local or std.$MACHINE.  The em-
     bedded config file can be extracted from the resulting kernel by the fol-
     lowing command:

           strings netbsd | sed -n 's/^_CFG_//p' | unvis

     options INCLUDE_JUST_CONFIG
     Similar to the above option, but includes just the actual config file,
     not any included files.

     options PIPE_SOCKETPAIR
     Use slower, but smaller socketpair(2)-based pipe implementation instead
     of default faster, but bigger one. Primarily useful for installation ker-
     nels.

     options USERCONF
     Compiles in the in-kernel device configuration manager.  See userconf(4)
     for details.

     options PERFCTRS
     Compiles in kernel support for CPU performance-monitoring counters.  See
     pmc(1) for details.  NOTE: not available on all architectures.

   Networking Options

     options GATEWAY
     Enables IPFORWARDING (which see) and (on most ports) increases the size
     of NMBCLUSTERS (which see).  In general, GATEWAY is used to indicate that
     a system should act as a router, and IPFORWARDING is not invoked direct-
     ly.  (Note that GATEWAY has no impact on protocols other than IP, such as
     CLNP or XNS).

     options IPFORWARDING=value
     If value is 1 this enables IP routing behavior. If value is 0 (the de-
     fault), it disables it. The GATEWAY option sets this to 1 automatically.
     With this option enabled, the machine will forward IP datagrams destined
     for other machines between its interfaces.  Note that even without this
     option, the kernel will still forward some packets (such as source routed
     packets) -- removing GATEWAY and IPFORWARDING is insufficient to stop all
     routing through a bastion host on a firewall -- source routing is con-
     trolled independently.  To turn off source routing, use options
     IPFORWSRCRT=0 (which see).  Note that IP forwarding may be turned on and
     off independently of the setting of the IPFORWARDING option through the
     use of the net.inet.ip.forwarding sysctl variable.  If
     net.inet.ip.forwarding is 1, IP forwarding is on.  See sysctl(8) and
     sysctl(3) for details.

     options IPFORWSRCRT=value
     If value is set to zero, source routing of IP datagrams is turned off.
     If value is set to one (the default) or the option is absent, source
     routed IP datagrams are forwarded by the machine.  Note that source rout-
     ing of IP packets may be turned on and off independently of the setting
     of the IPFORWSRCRT option through the use of the net.inet.ip.forwsrcrt
     sysctl variable.  If net.inet.ip.forwsrcrt is 1, forwarding of source
     routed IP datagrams is on.  See sysctl(8) and sysctl(3) for details.

     options IFA_STATS
     Tells the kernel to maintain per-address statistics on bytes sent and re-
     ceived over (currently) internet and appletalk addresses.  The option is
     not recommended as it degrades system stability.

     options MROUTING
     Includes support for IP multicast routers.  You certainly want INET with
     this.  Multicast routing is controlled by the mrouted(8) daemon.

     options INET
     Includes support for the TCP/IP protocol stack.  You almost certainly
     want this.  See inet(4) for details.  This option is currently required.

     options INET6
     Includes support for the IPv6 protocol stack.  See inet6(4) for details.
     Unlike INET, INET6 enables multicast routing code as well.  This option
     requires INET at this moment, but it should not.

     options ND6_DEBUG
     The option sets the default value of net.inet6.icmp6.nd6_debug to 1, for
     debugging IPv6 neighbor discovery protocol handling.  See sysctl(3) for
     details.

     options IPSEC
     Includes support for the IPsec protocol.  See ipsec(4) for details.
     IPSEC will enable secret key management part, policy management part, AH
     and IPComp.  Kernel binary will not be subject to export control in most
     of countries, even if compiled with IPSEC.  For example, it should be
     okay to export it from within the United States to the outside.  INET6
     and IPSEC are orthogonal so you can get IPv4-only kernel with IPsec sup-
     port, IPv4/v6 dual support kernel without IPsec, and so forth.  This op-
     tion requires INET at this moment, but it should not.

     options IPSEC_DEBUG
     Enables debugging code in IPsec stack.  This option assumes IPSEC.

     options IPSEC_ESP
     Includes support for IPsec ESP protocol.  See ipsec(4) for details.
     IPSEC_ESP will enable source code that is subject to export control in
     some countries (including the United States), and compiled kernel binary
     will be subject to certain restriction.  This option assumes IPSEC.

     options SUBNETSARELOCAL
     Sets default value for net.inet.ip.subnetsarelocal variable, which con-
     trols whether non-directly-connected subnets of connected networks are
     considered "local" for purposes of choosing the MSS for a TCP connection.
     This is mostly present for historic reasons and completely irrelevant if
     you enable Path MTU discovery.

     options HOSTZEROBROADCAST
     Sets default value for net.inet.ip.hostzerobroadcast variable, which con-
     trols whether the zeroth host address of each connected subnet is also
     considered a broadcast address.  Default value is "1", for compatibility
     with old systems; if this is set to zero on all hosts on a subnet, you
     should be able to fit an extra host per subnet on the ".0" address.

     options MCLSHIFT=value
     This option is the base-2 logarithm of the size of mbuf clusters.  The
     BSD networking stack keeps network packets in a linked list, or chain, of
     kernel buffer objects called mbufs.  The system provides larger mbuf
     clusters as an optimization for large packets, instead of using long
     chains for large packets.  The mbuf cluster size, or MCLBYTES, must be a
     power of two, and is computed as two raised to the power MCLSHIFT.  On
     systems with Ethernet network adaptors, MCLSHIFT is often set to 11, giv-
     ing 2048-byte mbuf clusters, large enough to hold a 1500-byte Ethernet
     frame in a single cluster.  Systems with network interfaces supporting
     larger frame sizes like ATM, FDDI, or HIPPI may perform better with
     MCLSHIFT set to 12 or 13, giving mbuf cluster sizes of 4096 and 8192
     bytes, respectively.

     options NS
     Include support for the Xerox XNS protocol stack.  See ns(4) for details.

     options ISO,TPIP
     Include support for the ubiquitous OSI protocol stack.  See iso(4) for
     details.  This option assumes INET.

     options EON
     Include support for tunneling OSI protocols over IP.  Known to be broken,
     or at least very fragile, and undocumented.

     options CCITT,LLC,HDLC
     Include support for the CCITT (nee ITU-TSS) X.25 protocol stack.  The
     state of this code is currently unknown, and probably contains bugs.
     This option assumes INET.

     options NETATALK
     Include support for the AppleTalk protocol stack.  The kernel provides
     provision for the Datagram Delivery Protocol (DDP), providing SOCK_DGRAM
     support and AppleTalk routing.  This stack is used by the NETATALK pack-
     age, which adds support for AppleTalk server services via user libraries
     and applications.

     options IPNOPRIVPORTS
     Normally, only root can bind a socket descriptor to a so-called
     ``privileged'' TCP port, that is, a port number in the range 0-1023.
     This option eliminates those checks from the kernel.  This can be useful
     if there is a desire to allow daemons without privileges to bind those
     ports, e.g. on firewalls.  The security tradeoffs in doing this are sub-
     tle.  This option should only be used by experts.

     options TCP_COMPAT_42
     TCP bug compatibility with 4.2BSD.  In 4.2BSD, TCP sequence numbers were
     32-bit signed values.  Modern implementations of TCP use unsigned values.
     This option clamps the initial sequence number to start in the range 2^31
     rather than the full unsigned range of 2^32.  Also, under 4.2BSD,
     keepalive packets must contain at least one byte or else the remote end
     would not respond.

     options TCP_DEBUG
     Record the last TCP_NDEBUG TCP packets with SO_DEBUG set, and decode to
     the console if tcpconsdebug is set.

     options TCP_NDEBUG
     Number of packets to record for TCP_DEBUG.  Defaults to 100.

     options PFIL_HOOKS
     This option turns on the packet filter interface hooks.  See pfil(9) for
     details.  This option assumes INET.

     options IPFILTER_LOG
     This option, in conjunction with pseudo-device ipfilter, enables logging
     of IP packets using ip-filter.

     options IPFILTER_DEFAULT_BLOCK
     This option sets the default policy of ip-filter.  If it is set, ip-fil-
     ter will block packets by default.

     options PPP_BSDCOMP
     Enable support for BSD-compress (`bsdcomp') compression in ppp.

     options PPP_DEFLATE
     Enable support for deflate compression in ppp.

     options PPP_FILTER
     This option turns on pcap(3) based filtering for ppp connections.  This
     option is used by pppd(8) which needs to be compiled with PPP_FILTER de-
     fined (the current default).

   System V IPC Options

     options SYSVMSG
     Includes support for AT&T System V UNIX style message queues.  See
     msgctl(2), msgget(2), msgrcv(2), msgsnd(2).

     options SYSVSEM
     Includes support for AT&T System V UNIX style semaphores.  See semctl(2),
     semget(2), semop(2).

     options SEMMNI=value
     Sets the number of AT&T System V UNIX style semaphore identifiers.  The
     GENERIC config file for your port will have the default.

     options SEMMNS=value
     Sets the number of AT&T System V UNIX style semaphores in the system.
     The GENERIC config file for your port will have the default.

     options SEMUME=value
     Sets the maximum number of undo entries per process for AT&T System V
     UNIX style semaphores.  The GENERIC config file for your port will have
     the default.

     options SEMMNU=value
     Sets the number of undo structures in the system for AT&T System V UNIX
     style semaphores.  The GENERIC config file for your port will have the
     default.

     options SYSVSHM
     Includes support for AT&T System V UNIX style shared memory.  See
     shmat(2), shmctl(2), shmdt(2), shmget(2).

     options SHMMAXPGS=value
     Sets the maximum number of AT&T System V UNIX style shared memory pages
     that are available through the shmget(2) system call.  Default value is
     1024 on most ports.  See /usr/include/machine/vmparam.h for the default.

   VM Related Options

     options NMBCLUSTERS=value
     The number of mbuf clusters the kernel supports.  Mbuf clusters are
     MCLBYTES in size (usually 2k).  This is used to compute the size of the
     kernel VM map mb_map, which maps mbuf clusters.  Default on most ports is
     256 (512 with ``options GATEWAY'' ).  See /usr/include/machine/param.h
     for exact default information.  Increase this value if you get ``mb_map
     full'' messages.

     options NKMEMPAGES=value

     options NKMEMPAGES_MIN=value

     options NKMEMPAGES_MAX=value
     Size of kernel VM map kmem_map, in PAGE_SIZE-sized chunks (the VM page
     size; this value may be read from the sysctl(8) variable hw.pagesize ).
     This VM map is used to map the kernel malloc arena.  The kernel attempts
     to auto-size this map based on the amount of physical memory in the sys-
     tem.  Platform-specific code may place bounds on this computed size,
     which may be viewed with the sysctl(8) variable vm.nkmempages.  See
     /usr/include/machine/param.h for the default upper and lower bounds.  The
     related options `NKMEMPAGES_MIN' and `NKMEMPAGES_MAX' allow the bounds to
     be overridden in the kernel configuration file.  These options are pro-
     vided in the event the computed value is insufficient resulting in an
     ``out of space in kmem_map'' panic.

     options BUFCACHE=value
     Size of the buffer cache as a percentage of total available RAM.  Ignored
     if BUFPAGES is also specified.

     options NBUF=value

     options BUFPAGES=value
     These options set the number of pages available for the buffer cache.
     Their default value is a machine dependent value, often calculated as be-
     tween 5% and 10% of total available RAM.

     options MAXTSIZ=bytes
     Sets the maximum size limit of a process' text segment. See
     /usr/include/machine/vmparam.h for the port-specific default.

     options DFLDSIZ=bytes
     Sets the default size limit of a process' data segment, the value that
     will be returned as the soft limit for RLIMIT_DATA (as returned by
     getrlimit(2)).  See /usr/include/machine/vmparam.h for the port-specific
     default.

     options MAXDSIZ=bytes
     Sets the maximum size limit of a process' data segment, the value that
     will be returned as the hard limit for RLIMIT_DATA (as returned by
     getrlimit(2)).  See /usr/include/machine/vmparam.h for the port-specific
     default.

     options DFLSSIZ=bytes
     Sets the default size limit of a process' stack segment, the value that
     will be returned as the soft limit for RLIMIT_STACK (as returned by
     getrlimit(2)).  See /usr/include/machine/vmparam.h for the port-specific
     default.

     options MAXSSIZ=bytes
     Sets the maximum size limit of a process' stack segment, the value that
     will be returned as the hard limit for RLIMIT_STACK (as returned by
     getrlimit(2)).  See /usr/include/machine/vmparam.h for the port-specific
     default.

   amiga-specific Options

     options BB060STUPIDROM
     When the bootloader (which passes AmigaOS ROM information) claims we have
     a 68060 CPU without FPU, go look into the Processor Configuration Regis-
     ter (PCR) to find out.  You need this with Amiga ROMs up to (at least)
     V40.xxx (OS3.1), when you boot via the bootblocks and don't have a DraCo.

     options IOBZCLOCK=frequency
     The IOBlix boards come with two different serial master clocks: older
     ones use 24 MHz, newer ones use 22.1184 MHz. The driver normally assumes
     the latter.  If your board uses 24 MHz, you can recompile your kernel
     with options IOBZCLOCK=24000000 or patch the kernel variable iobzclock to
     the same value.

     options LIMITMEM=value
     If there, limit the part of the first memory bank used by NetBSD to value
     megabytes.  Default is unlimited.

     options NKPTADD=addvalue

     options NKPTADDSHIFT=shiftvalue
     The CPU specific MMU table for the kernel is pre-allocated at kernel
     startup time.  Part of it is scaled with maxproc, to have enough room to
     hold the user program MMU tables; the second part is a fixed amount for
     the kernel itself.

     The third part accounts for the size of the file buffer cache.  Its size
     is either NKPTADD pages (if defined) or memory size in bytes divided by
     two to the power of NKPTADDSHIFT.  The default is undefined NKPTADD and
     NKPTADDSHIFT=24, allowing for 16 buffers per megabyte of main memory
     (while a GENERIC kernel allocates about half of that).  When you get
     "can't get KPT page" panics, you should increase NKPTADD (if defined), or
     decrease NKPTADDSHIFT by one.

     options P5PPC68KBOARD
     Add special support for Phase5 mixed 68k+PPC boards. Currently, this only
     affects rebooting from NetBSD and is only needed on 68040+PPC, not on
     68060+PPC; without this, affected machines will hang after NetBSD has
     shut down and will only restart after a keyboard reset or a power cycle.

   arm32-specific Options

     options FRENCH_KEYBOARD
     Include translation for French keyboards when using pccons(4) on a Shark.

     options FINNISH_KEYBOARD
     Include translation for Finnish keyboards when using pccons(4) on a
     Shark.

     options GERMAN_KEYBOARD
     Include translation for German keyboards when using pccons(4) on a Shark.

     options NORWEGIAN_KEYBOARD
     Include translation for French keyboards when using pccons(4) on a Shark.

   atari-specific Options

     options DISKLABEL_AHDI
     Include support for AHDI (native Atari) disklabels.

     options DISKLABEL_NBDA
     Include support for NetBSD/atari labels.  If you don't set this option,
     it will be set automatically.  NetBSD/atari will not work without it.

     options FALCON_SCSI
     Include support for the 5380-SCSI configuration as found on the Falcon.

     options RELOC_KERNEL
     If set, the kernel will relocate itself to TT-RAM, if possible.  This
     will give you a slightly faster system.  Beware that on some TT030 sys-
     tems, the system will frequently dump with MMU-faults with this option
     enabled.

     options SERCONSOLE
     Allow the modem1-port to act as the system-console.  A carrier should be
     active on modem1 during system boot to active the console functionality.

     options TT_SCSI
     Include support for the 5380-SCSI configuration as found on the TT030 and
     Hades.

   i386-specific Options

     options I386_CPU,I486_CPU,I586_CPU,I686_CPU
     Include support for a particular class of CPU (i386, i486, Pentium, or
     Pentium Pro).  If the appropriate class for your CPU is not configured,
     the kernel will use the highest class available that will work.  In gen-
     eral, using the correct CPU class will result in the best performance.
     At least one of these options must be present.

     options CPURESET_DELAY=value
     specifies the time (in millisecond) to wait before doing a hardware reset
     in the last phase of a reboot. This gives the user a chance to see error
     messages from the shutdown operations (like NFS unmounts, buffer cache
     flush, etc ...). Setting this to 0 will disable the delay. Default is 2
     seconds.

     options MATH_EMULATE
     Include the floating point emulator.  This is useful only for CPUs that
     lack an internal Floating Point Unit (FPU) or co-processor.

     options VM86
     Include support for virtual 8086 mode, used by DOS emulators and X
     servers to run BIOS code, e.g. for some VESA routines.

     options USER_LDT
     Include i386-specific system calls for modifying the local descriptor
     table, used by Windows emulators.

     options REALBASEMEM=integer
     Overrides the base memory size passed in from the boot block.  (Value
     given in kilobytes.)  Use this option only if the boot block reports the
     size incorrectly.  (Note that some BIOSes put the extended BIOS data area
     at the top of base memory, and therefore report a smaller base memory
     size to prevent programs overwriting it.  This is correct behavior, and
     you should not use the REALBASEMEM option to access this memory).

     options REALEXTMEM=integer
     Overrides the extended memory size passed in from the boot block.  (Value
     given in kilobytes. Extended memory does not include the first megabyte.)
     Use this option only if the boot block reports the size incorrectly.

     options FRENCH_KBD,FINNISH_KBD,GERMAN_KBD,NORWEGIAN_KBD
     Select a non-US keyboard layout for the pccons console driver.

     options CYRIX_CACHE_WORKS
     Relevant only to the Cyrix 486DLC cpu. This option is used to turn on the
     cache in hold-flush mode. It is not turned on by default because it is
     known to have problems in certain motherboard implementations.

     options CYRIX_CACHE_REALLY_WORKS
     Relevant only to the Cyrix 486DLC cpu. This option is used to turn on the
     cache in write-back mode. It is not turned on by default because it is
     known to have problems in certain motherboard implementations. In order
     for this option to take effect, option CYRIX_CACHE_WORKS must also be
     specified.

     options PCIBIOS
     Enable support for initializing the PCI bus using information from the
     BIOS.  See pcibios(4) for details.

   isa-specific Options
     Options specific to isa(4) busses.

     options PCIC_ISA_ALLOC_IOBASE=address, PCIC_ISA_ALLOC_IOSIZE=size
     Control the section of IO bus space used for PCMCIA bus space mapping.
     Ideally the probed defaults are satisfactory, however in practice that is
     not always the case. See pcmcia(4) for details.

     options PCIC_ISA_INTR_ALLOC_MASK=mask
     Controls the allowable interrupts that may be used for PCMCIA devices.
     This mask is a logical-or of power-of-2s of allowable interrupts:

        IRQ Val      IRQ Val      IRQ Val       IRQ Val
         0  0x0001    4  0x0010    8  0x0100    12  0x1000
         1  0x0002    5  0x0020    9  0x0200    13  0x2000
         2  0x0004    6  0x0040   10  0x0400    14  0x4000
         3  0x0008    7  0x0080   11  0x0800    15  0x8000

   m68k-specific Options

     options FPU_EMULATE
     Include support for MC68881/MC68882 emulator.

     options FPSP
     Include support for 68040 floating point.

     options M68020,M68030,M68040,M68060
     Include support for a specific CPU, at least one (the one you are using)
     should be specified.

     options M060SP
     Include software support for 68060.  This provides emulation of unimple-
     mented integer instructions as well as emulation of unimplemented float-
     ing point instructions and data types and software support for floating
     point traps.

   sparc-specific Options

     options AUDIO_DEBUG
     Enable simple event debugging of the logging of the audio(4) device.

     options BLINK
     Enable blinking of LED.  Blink rate is full cycle every N seconds for N <
     then current load average.  See getloadavg(3).

     options COUNT_SW_LEFTOVERS
     Count how many times the sw SCSI device has left 3, 2, 1 and 0 in the
     sw_3_leftover, sw_2_leftover, sw_1_leftover, and sw_0_leftover variables
     accessible from ddb(4).  See sw(4).

     options DEBUG_ALIGN
     Adds debugging messages calls when user-requested alignment fault han-
     dling happens.

     options DEBUG_EMUL
     Adds debugging messages calls for emulated floating point and alignment
     fixing operations.

     options DEBUG_SVR4
     Prints registers messages calls for emulated SVR4 getcontext and setcon-
     text operations.  See options COMPAT_SVR4.

     options EXTREME_DEBUG
     Adds debugging functions callable from ddb(4). The debug_pagetables,
     test_region and print_fe_map functions print information about page ta-
     bles for the SUN4M platforms only.

     options EXTREME_EXTREME_DEBUG
     Adds extra info to options EXTREME_DEBUG.

     options FPU_CONTEXT
     Make options COMPAT_SVR4 getcontext and setcontext include floating point
     registers.

     options MAGMA_DEBUG
     Adds debugging messages to the magma(4) device.

     options RASTERCONS_FULLSCREEN
     Use the entire screen for the console.

     options RASTERCONS_SMALLFONT
     Use a the fixed font on the console, instead of the normal font.

     options SUN4
     Support sun4 class machines.

     options SUN4C
     Support sun4c class machines.

     options SUN4M
     Support sun4m class machines.

     options SUN4_MMU3L
     Enable support for sun4 3-level MMU machines.

     options V9
     Enable SPARC V9 assembler in ddb(4).

   sparc64-specific Options

     options AUDIO_DEBUG
     Enable simple event debugging of the logging of the audio(4) device.

     options BLINK
     Enable blinking of LED.  Blink rate is full cycle every N seconds for N <
     then current load average.  See getloadavg(3).

   x68k-specific Options

     options EXTENDED_MEMORY
     Include support for extended memory e.g. TS-6BE16 and 060turbo on-board.

     options JUPITER
     Include support for Jupiter-X MPU accelerator

     options ZSCONSOLE,ZSCN_SPEED=value
     Use the built-in serial port as the system-console.  Speed is specified
     in bps, defaults to 9600.

     options ITE_KERNEL_ATTR=value
     Set the kernel message attribute for ITE.  Value, an integer, is a logi-
     cal or of the following values:
           1     color inversed
           2     underlined
           4     bolded

SEE ALSO
     gdb(1), ktrace(1), quota(1), pmc(1), gettimeofday(2), i386_iopl(2),
     msgctl(2), msgget(2), msgrcv(2), msgsnd(2), ntp_adjtime(2),
     ntp_gettime(2), semctl(2), semget(2), semop(2), shmat(2), shmctl(2),
     shmdt(2), shmget(2), sysctl(3), apm(4), ddb(4), inet(4), iso(4), lkm(4),
     md(4), ns(4), pcibios(4), pcmcia(4), userconf(4), config(8), edquota(8),
     init(8), mdsetimage(8), mount_cd9660(8), mount_fdesc(8), mount_kernfs(8),
     mount_lfs(8), mount_mfs(8), mount_msdos(8), mount_nfs(8), mount_ntfs(8),
     mount_null(8), mount_portal(8), mount_procfs(8), mount_umap(8),
     mount_union(8), mrouted(8), newfs_lfs(8), ntpd(8), quotaon(8),
     rpc.rquotad(8), sysctl(8)

HISTORY
     The options man page first appeared in NetBSD 1.3.

BUGS
     The INET and the VNODEPAGER options should not be required.  The EON op-
     tion should be a pseudo-device, and is also very fragile.

NetBSD 1.6                     November 20, 2001                            19

You can also request any man page by name and (optionally) by section:

Command: 
Section: 
Architecture: 
Collection: 
 

Use the DEFAULT collection to view manual pages for third-party software.


©1994 Man-cgi 1.15, Panagiotis Christias <christia@softlab.ntua.gr>
©1996-2014 Modified for NetBSD by Kimmo Suominen