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#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#
menu "Linux System Utilities"
config CONFIG_DMESG
bool "dmesg"
default n
help
dmesg is used to examine or control the kernel ring buffer. When the
Linux kernel prints messages to the system log, they are stored in
the kernel ring buffer. You can use dmesg to print the kernel's ring
buffer, clear the kernel ring buffer, change the size of the kernel
ring buffer, and change the priority level at which kernel messages
are also logged to the system console. Enable this option if you
wish to enable the 'dmesg' utility.
config CONFIG_FBSET
bool "fbset"
default n
help
fbset is used to show or change the settings of a Linux frame buffer
device. The frame buffer device provides a simple and unique
interface to access a graphics display. Enable this option
if you wish to enable the 'fbset' utility.
config CONFIG_FEATURE_FBSET_FANCY
bool " Turn on extra fbset options"
default n
depends on CONFIG_FBSET
help
This option enables extended fbset options, allowing one to set the
framebuffer size, color depth, etc. interface to access a graphics
display. Enable this option if you wish to enable extended fbset
options.
config CONFIG_FEATURE_FBSET_READMODE
bool " Turn on fbset readmode support"
default n
depends on CONFIG_FBSET
help
This option allows fbset to read the video mode database stored by
default as /etc/fb.modes, which can be used to set frame buffer
device to pre-defined video modes.
config CONFIG_FDFLUSH
bool "fdflush"
default n
help
fdflush is only needed when changing media on slightly-broken
removable media drives. It is used to make Linux believe that a
hardware disk-change switch has been actuated, which causes Linux to
forget anything it has cached from the previous media. If you have
such a slightly-broken drive, you will need to run fdflush every time
you change a disk. Most people have working hardware and can safely
leave this disabled.
config CONFIG_FDFORMAT
bool "fdformat"
default n
help
fdformat is used to low-level format a floppy disk.
config CONFIG_FDISK
bool "fdisk"
default n
help
The fdisk utility is used to divide hard disks into one or more
logical disks, which are generally called partitions. This utility
can be used to list and edit the set of partitions or BSD style
'disk slices' that are defined on a hard drive.
config FDISK_SUPPORT_LARGE_DISKS
bool " support over 4GB disks"
default y
depends on CONFIG_FDISK
help
Enable this option to support large disks > 4GB.
config CONFIG_FEATURE_FDISK_WRITABLE
bool " Write support"
default y
depends on CONFIG_FDISK
help
Enabling this option allows you to create or change a partition table
and write those changes out to disk. If you leave this option
disabled, you will only be able to view the partition table.
config CONFIG_FEATURE_AIX_LABEL
bool " Support AIX disklabels"
default n
depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
help
Enabling this option allows you to create or change AIX disklabels.
Most people can safely leave this option disabled.
config CONFIG_FEATURE_SGI_LABEL
bool " Support SGI disklabels"
default n
depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
help
Enabling this option allows you to create or change SGI disklabels.
Most people can safely leave this option disabled.
config CONFIG_FEATURE_SUN_LABEL
bool " Support SUN disklabels"
default n
depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
help
Enabling this option allows you to create or change SUN disklabels.
Most people can safely leave this option disabled.
config CONFIG_FEATURE_OSF_LABEL
bool " Support BSD disklabels"
default n
depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
help
Enabling this option allows you to create or change BSD disklabels
and define and edit BSD disk slices.
config CONFIG_FEATURE_FDISK_ADVANCED
bool " Support expert mode"
default n
depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
help
Enabling this option allows you to do terribly unsafe things like
define arbitrary drive geometry, move the beginning of data in a
partition, and similarly evil things. Unless you have a very good
reason you would be wise to leave this disabled.
config CONFIG_FREERAMDISK
bool "freeramdisk"
default n
help
Linux allows you to create ramdisks. This utility allows you to
delete them and completely free all memory that was used for the
ramdisk. For example, if you boot Linux into a ramdisk and later
pivot_root, you may want to free the memory that is allocated to the
ramdisk. If you have no use for freeing memory from a ramdisk, leave
this disabled.
config CONFIG_FSCK_MINIX
bool "fsck_minix"
default n
help
The minix filesystem is a nice, small, compact, read-write filesystem
with little overhead. It is not a journaling filesystem however and
can experience corruption if it is not properly unmounted or if the
power goes off in the middle of a write. This utility allows you to
check for and attempt to repair any corruption that occurs to a minix
filesystem.
config CONFIG_MKFS_MINIX
bool "mkfs_minix"
default n
help
The minix filesystem is a nice, small, compact, read-write filesystem
with little overhead. If you wish to be able to create minix filesystems
this utility will do the job for you.
comment "Minix filesystem support"
depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
config CONFIG_FEATURE_MINIX2
bool " Support Minix fs v2 (fsck_minix/mkfs_minix)"
default y
depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
help
If you wish to be able to create version 2 minix filesystems, enable this.
If you enabled 'mkfs_minix' then you almost certainly want to be using the
version 2 filesystem support.
config CONFIG_GETOPT
bool "getopt"
default n
help
The getopt utility is used to break up (parse) options in command
lines to make it easy to write complex shell scripts that also check
for legal (and illegal) options. If you want to write horribly
complex shell scripts, or use some horribly complex shell script
written by others, this utility may be for you. Most people will
wisely leave this disabled.
config CONFIG_HEXDUMP
bool "hexdump"
default n
help
The hexdump utility is used to display binary data in a readable
way that is comparable to the output from most hex editors.
config CONFIG_HWCLOCK
bool "hwclock"
default n
help
The hwclock utility is used to read and set the hardware clock
on a system. This is primarily used to set the current time on
shutdown in the hardware clock, so the hardware will keep the
correct time when Linux is _not_ running.
config CONFIG_FEATURE_HWCLOCK_LONGOPTIONS
bool " Support long options (--hctosys,...)"
default n
depends on CONFIG_HWCLOCK
help
By default, the hwclock utility only uses short options. If you
are overly fond of its long options, such as --hctosys, --utc, etc)
then enable this option.
config CONFIG_FEATURE_HWCLOCK_ADJTIME_FHS
bool " Use FHS /var/lib/hwclock/adjtime"
default y
depends on CONFIG_HWCLOCK
help
Starting with FHS 2.3, the adjtime state file is supposed to exist
at /var/lib/hwclock/adjtime instead of /etc/adjtime. If you wish
to use the FHS behavior, answer Y here, otherwise answer N for the
classic /etc/adjtime path.
http://www.pathname.com/fhs/pub/fhs-2.3.html#VARLIBHWCLOCKSTATEDIRECTORYFORHWCLO
config CONFIG_IPCRM
bool "ipcrm"
default n
select CONFIG_FEATURE_SUID
help
The ipcrm utility allows the removal of System V interprocess
communication (IPC) objects and the associated data structures
from the system.
config CONFIG_IPCS
bool "ipcs"
default n
select CONFIG_FEATURE_SUID
help
The ipcs utility is used to provide information on the currently
allocated System V interprocess (IPC) objects in the system.
config CONFIG_LOSETUP
bool "losetup"
default n
help
losetup is used to associate or detach a loop device with a regular
file or block device, and to query the status of a loop device. This
version does not currently support enabling data encryption.
config CONFIG_MDEV
bool "mdev"
default n
help
mdev is a mini-udev implementation: call it with -s to populate
/dev from /sys, then "echo /sbin/mdev > /proc/sys/kernel/hotplug" to
have it handle hotplug events afterwards. Device names are taken
from sysfs.
config CONFIG_FEATURE_MDEV_CONF
bool " Support /etc/mdev.conf"
default n
depends on CONFIG_MDEV
help
The mdev config file contains lines that look like:
hd[a-z][0-9]* 0:3 660
That's device name (with regex match), uid:gid, and permissions.
Optionally, that can be followed (on the same line) by an asterisk
and a command line to run after creating the corresponding device(s),
ala:
hdc root:cdrom 660 *ln -s hdc cdrom
Config file parsing stops on the first matching line. If no config
entry is matched, devices are created with default 0:0 660. (Make
the last line match .* to override this.)
config CONFIG_MKSWAP
bool "mkswap"
default n
help
The mkswap utility is used to configure a file or disk partition as
Linux swap space. This allows Linux to use the entire file or
partition as if it were additional RAM, which can greatly increase
the capability of low-memory machines. This additional memory is
much slower than real RAM, but can be very helpful at preventing your
applications being killed by the Linux out of memory (OOM) killer.
Once you have created swap space using 'mkswap' you need to enable
the swap space using the 'swapon' utility.
config CONFIG_MORE
bool "more"
default n
help
more is a simple utility which allows you to read text one screen
sized page at a time. If you want to read text that is larger than
the screen, and you are using anything faster than a 300 baud modem,
you will probably find this utility very helpful. If you don't have
any need to reading text files, you can leave this disabled.
config CONFIG_FEATURE_USE_TERMIOS
bool " Use termios to manipulate the screen"
default y
depends on CONFIG_MORE
help
This option allows utilities such as 'more' and 'top' to determine
the size of the screen. If you leave this disabled, your utilities
that display things on the screen will be especially primitive and
will be unable to determine the current screen size, and will be
unable to move the cursor.
config CONFIG_MOUNT
bool "mount"
default n
help
All files and filesystems in Unix are arranged into one big directory
tree. The 'mount' utility is used to graft a filesystem onto a
particular part of the tree. A filesystem can either live on a block
device, or it can be accessible over the network, as is the case with
NFS filesystems. Most people using BusyBox will also want to enable
the 'mount' utility.
config CONFIG_FEATURE_MOUNT_NFS
bool " Support mounting NFS file systems"
default n
depends on CONFIG_MOUNT
help
Enable mounting of NFS file systems.
config CONFIG_PIVOT_ROOT
bool "pivot_root"
default n
help
The pivot_root utility swaps the mount points for the root filesystem
with some other mounted filesystem. This allows you to do all sorts
of wild and crazy things with your Linux system and is far more
powerful than 'chroot'.
Note: This is for initrd in linux 2.4. Under initramfs (introduced
in linux 2.6) use switch_root instead.
config CONFIG_RDATE
bool "rdate"
default n
help
The rdate utility allows you to synchronize the date and time of your
system clock with the date and time of a remote networked system using
the RFC868 protocol, which is built into the inetd daemon on most
systems.
config CONFIG_READPROFILE
bool "readprofile"
default n
help
This allows you to parse /proc/profile for basic profiling.
config CONFIG_LINUX32
default n
depends on CONFIG_SETARCH
config CONFIG_LINUX64
default n
depends on CONFIG_SETARCH
config CONFIG_SETARCH
bool "setarch"
default n
select CONFIG_LINUX32
select CONFIG_LINUX64
help
The linux32 utility is used to create a 32bit environment for the
specified program (usually a shell). It only makes sense to have
this util on a system that supports both 64bit and 32bit userland
(like amd64/x86, ppc64/ppc, sparc64/sparc, etc...).
config CONFIG_SWAPONOFF
bool "swaponoff"
default n
help
This option enables both the 'swapon' and the 'swapoff' utilities.
Once you have created some swap space using 'mkswap', you also need
to enable your swap space with the 'swapon' utility. The 'swapoff'
utility is used, typically at system shutdown, to disable any swap
space. If you are not using any swap space, you can leave this
option disabled.
config CONFIG_SWITCH_ROOT
bool "switch_root"
default n
help
The switch_root utility is used from initramfs to select a new
root device. Under initramfs, you have to use this instead of
pivot_root. (Stop reading here if you don't care why.)
Booting with initramfs extracts a gzipped cpio archive into rootfs
(which is a variant of ramfs/tmpfs). Because rootfs can't be moved
or unmounted*, pivot_root will not work from initramfs. Instead,
switch_root deletes everything out of rootfs (including itself),
does a mount --move that overmounts rootfs with the new root, and
then execs the specified init program.
* Because the Linux kernel uses rootfs internally as the starting
and ending point for searching through the kernel's doubly linked
list of active mount points. That's why.
config CONFIG_UMOUNT
bool "umount"
default n
help
When you want to remove a mounted filesystem from its current mount point,
for example when you are shutting down the system, the 'umount' utility is
the tool to use. If you enabled the 'mount' utility, you almost certainly
also want to enable 'umount'.
config CONFIG_FEATURE_UMOUNT_ALL
bool " umount -a option"
default n
depends on CONFIG_UMOUNT
help
Support -a option to unmount all currently mounted filesystems.
comment "Common options for mount/umount"
depends on CONFIG_MOUNT || CONFIG_UMOUNT
config CONFIG_FEATURE_MOUNT_LOOP
bool " Support loopback mounts"
default n
depends on CONFIG_MOUNT || CONFIG_UMOUNT
help
Enabling this feature allows automatic mounting of files (containing
filesystem images) via the linux kernel's loopback devices. The mount
command will detect you are trying to mount a file instead of a block
device, and transparently associate the file with a loopback device.
The umount command will also free that loopback device.
You can still use the 'losetup' utility (to manually associate files
with loop devices) if you need to do something advanced, such as
specify an offset or cryptographic options to the loopback device.
(If you don't want umount to free the loop device, use "umount -D".)
config CONFIG_FEATURE_MTAB_SUPPORT
bool " Support for the old /etc/mtab file"
default n
depends on CONFIG_MOUNT || CONFIG_UMOUNT
help
Historically, Unix systems kept track of the currently mounted
partitions in the file "/etc/mtab". These days, the kernel exports
the list of currently mounted partitions in "/proc/mounts", rendering
the old mtab file obsolete. (In modern systems, /etc/mtab should be
a symlink to /proc/mounts.)
The only reason to have mount maintain an /etc/mtab file itself is if
your stripped-down embedded system does not have a /proc directory.
If you must use this, keep in mind it's inherently brittle (for
example a mount under chroot won't update it), can't handle modern
features like separate per-process filesystem namespaces, requires
that your /etc directory be writeable, tends to get easily confused
by --bind or --move mounts, and so on. (In brief: avoid.)
endmenu
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