2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
6 menu "Linux System Utilities"
12 dmesg is used to examine or control the kernel ring buffer. When the
13 Linux kernel prints messages to the system log, they are stored in
14 the kernel ring buffer. You can use dmesg to print the kernel's ring
15 buffer, clear the kernel ring buffer, change the size of the kernel
16 ring buffer, and change the priority level at which kernel messages
17 are also logged to the system console. Enable this option if you
18 wish to enable the 'dmesg' utility.
24 fbset is used to show or change the settings of a Linux frame buffer
25 device. The frame buffer device provides a simple and unique
26 interface to access a graphics display. Enable this option
27 if you wish to enable the 'fbset' utility.
29 config CONFIG_FEATURE_FBSET_FANCY
30 bool " Turn on extra fbset options"
32 depends on CONFIG_FBSET
34 This option enables extended fbset options, allowing one to set the
35 framebuffer size, color depth, etc. interface to access a graphics
36 display. Enable this option if you wish to enable extended fbset
39 config CONFIG_FEATURE_FBSET_READMODE
40 bool " Turn on fbset readmode support"
42 depends on CONFIG_FBSET
44 This option allows fbset to read the video mode database stored by
45 default as /etc/fb.modes, which can be used to set frame buffer
46 device to pre-defined video modes.
52 fdflush is only needed when changing media on slightly-broken
53 removable media drives. It is used to make Linux believe that a
54 hardware disk-change switch has been actuated, which causes Linux to
55 forget anything it has cached from the previous media. If you have
56 such a slightly-broken drive, you will need to run fdflush every time
57 you change a disk. Most people have working hardware and can safely
60 config CONFIG_FDFORMAT
64 fdformat is used to low-level format a floppy disk.
70 The fdisk utility is used to divide hard disks into one or more
71 logical disks, which are generally called partitions. This utility
72 can be used to list and edit the set of partitions or BSD style
73 'disk slices' that are defined on a hard drive.
75 config FDISK_SUPPORT_LARGE_DISKS
76 bool " support over 4GB disks"
78 depends on CONFIG_FDISK
80 Enable this option to support large disks > 4GB.
82 config CONFIG_FEATURE_FDISK_WRITABLE
85 depends on CONFIG_FDISK
87 Enabling this option allows you to create or change a partition table
88 and write those changes out to disk. If you leave this option
89 disabled, you will only be able to view the partition table.
91 config CONFIG_FEATURE_AIX_LABEL
92 bool " Support AIX disklabels"
94 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
96 Enabling this option allows you to create or change AIX disklabels.
97 Most people can safely leave this option disabled.
99 config CONFIG_FEATURE_SGI_LABEL
100 bool " Support SGI disklabels"
102 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
104 Enabling this option allows you to create or change SGI disklabels.
105 Most people can safely leave this option disabled.
107 config CONFIG_FEATURE_SUN_LABEL
108 bool " Support SUN disklabels"
110 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
112 Enabling this option allows you to create or change SUN disklabels.
113 Most people can safely leave this option disabled.
115 config CONFIG_FEATURE_OSF_LABEL
116 bool " Support BSD disklabels"
118 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
120 Enabling this option allows you to create or change BSD disklabels
121 and define and edit BSD disk slices.
123 config CONFIG_FEATURE_FDISK_ADVANCED
124 bool " Support expert mode"
126 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
128 Enabling this option allows you to do terribly unsafe things like
129 define arbitrary drive geometry, move the beginning of data in a
130 partition, and similarly evil things. Unless you have a very good
131 reason you would be wise to leave this disabled.
133 config CONFIG_FREERAMDISK
137 Linux allows you to create ramdisks. This utility allows you to
138 delete them and completely free all memory that was used for the
139 ramdisk. For example, if you boot Linux into a ramdisk and later
140 pivot_root, you may want to free the memory that is allocated to the
141 ramdisk. If you have no use for freeing memory from a ramdisk, leave
144 config CONFIG_FSCK_MINIX
148 The minix filesystem is a nice, small, compact, read-write filesystem
149 with little overhead. It is not a journaling filesystem however and
150 can experience corruption if it is not properly unmounted or if the
151 power goes off in the middle of a write. This utility allows you to
152 check for and attempt to repair any corruption that occurs to a minix
155 config CONFIG_MKFS_MINIX
159 The minix filesystem is a nice, small, compact, read-write filesystem
160 with little overhead. If you wish to be able to create minix filesystems
161 this utility will do the job for you.
163 comment "Minix filesystem support"
164 depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
166 config CONFIG_FEATURE_MINIX2
167 bool " Support Minix fs v2 (fsck_minix/mkfs_minix)"
169 depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
171 If you wish to be able to create version 2 minix filesystems, enable this.
172 If you enabled 'mkfs_minix' then you almost certainly want to be using the
173 version 2 filesystem support.
179 The getopt utility is used to break up (parse) options in command
180 lines to make it easy to write complex shell scripts that also check
181 for legal (and illegal) options. If you want to write horribly
182 complex shell scripts, or use some horribly complex shell script
183 written by others, this utility may be for you. Most people will
184 wisely leave this disabled.
186 config CONFIG_HEXDUMP
190 The hexdump utility is used to display binary data in a readable
191 way that is comparable to the output from most hex editors.
193 config CONFIG_HWCLOCK
197 The hwclock utility is used to read and set the hardware clock
198 on a system. This is primarily used to set the current time on
199 shutdown in the hardware clock, so the hardware will keep the
200 correct time when Linux is _not_ running.
202 config CONFIG_FEATURE_HWCLOCK_LONGOPTIONS
203 bool " Support long options (--hctosys,...)"
205 depends on CONFIG_HWCLOCK
207 By default, the hwclock utility only uses short options. If you
208 are overly fond of its long options, such as --hctosys, --utc, etc)
209 then enable this option.
211 config CONFIG_FEATURE_HWCLOCK_ADJTIME_FHS
212 bool " Use FHS /var/lib/hwclock/adjtime"
214 depends on CONFIG_HWCLOCK
216 Starting with FHS 2.3, the adjtime state file is supposed to exist
217 at /var/lib/hwclock/adjtime instead of /etc/adjtime. If you wish
218 to use the FHS behavior, answer Y here, otherwise answer N for the
219 classic /etc/adjtime path.
221 http://www.pathname.com/fhs/pub/fhs-2.3.html#VARLIBHWCLOCKSTATEDIRECTORYFORHWCLO
226 select CONFIG_FEATURE_SUID
228 The ipcrm utility allows the removal of System V interprocess
229 communication (IPC) objects and the associated data structures
235 select CONFIG_FEATURE_SUID
237 The ipcs utility is used to provide information on the currently
238 allocated System V interprocess (IPC) objects in the system.
240 config CONFIG_LOSETUP
244 losetup is used to associate or detach a loop device with a regular
245 file or block device, and to query the status of a loop device. This
246 version does not currently support enabling data encryption.
252 mdev is a mini-udev implementation: call it with -s to populate
253 /dev from /sys, then "echo /sbin/mdev > /sys/kernel/hotplug" to
254 have it handle hotplug events afterwards. Device names are taken
257 config CONFIG_FEATURE_MDEV_CONF
258 bool " Support /etc/mdev.conf"
260 depends on CONFIG_MDEV
262 The mdev config file contains lines that look like:
264 hd[a-z][0-9]* 0:3 660
266 That's device name (with regex match), uid:gid, and permissions.
268 Optionally, that can be followed (on the same line) by an asterisk
269 and a command line to run after creating the corresponding device(s),
272 hdc root:cdrom 660 *ln -s hdc cdrom
274 Config file parsing stops on the first matching line. If no config
275 entry is matched, devices are created with default 0:0 660. (Make
276 the last line match .* to override this.)
282 The mkswap utility is used to configure a file or disk partition as
283 Linux swap space. This allows Linux to use the entire file or
284 partition as if it were additional RAM, which can greatly increase
285 the capability of low-memory machines. This additional memory is
286 much slower than real RAM, but can be very helpful at preventing your
287 applications being killed by the Linux out of memory (OOM) killer.
288 Once you have created swap space using 'mkswap' you need to enable
289 the swap space using the 'swapon' utility.
295 more is a simple utility which allows you to read text one screen
296 sized page at a time. If you want to read text that is larger than
297 the screen, and you are using anything faster than a 300 baud modem,
298 you will probably find this utility very helpful. If you don't have
299 any need to reading text files, you can leave this disabled.
301 config CONFIG_FEATURE_USE_TERMIOS
302 bool " Use termios to manipulate the screen"
304 depends on CONFIG_MORE
306 This option allows utilities such as 'more' and 'top' to determine
307 the size of the screen. If you leave this disabled, your utilities
308 that display things on the screen will be especially primitive and
309 will be unable to determine the current screen size, and will be
310 unable to move the cursor.
312 config CONFIG_PIVOT_ROOT
316 The pivot_root utility swaps the mount points for the root filesystem
317 with some other mounted filesystem. This allows you to do all sorts
318 of wild and crazy things with your Linux system and is far more
319 powerful than 'chroot'.
321 Note: This is for initrd in linux 2.4. Under initramfs (introduced
322 in linux 2.6) use switch_root instead.
324 config CONFIG_SWITCH_ROOT
328 The switch_root utility is used from initramfs to select a new
329 root device. Under initramfs, you have to use this instead of
330 pivot_root. (Stop reading here if you don't care why.)
332 Booting with initramfs extracts a gzipped cpio archive into rootfs
333 (which is a variant of ramfs/tmpfs). Because rootfs can't be moved
334 or unmounted*, pivot_root will not work from initramfs. Instead,
335 switch_root deletes everything out of rootfs (including itself),
336 does a mount --move that overmounts rootfs with the new root, and
337 then execs the specified init program.
339 * Because the Linux kernel uses rootfs internally as the starting
340 and ending point for searching through the kernel's doubly linked
341 list of active mount points. That's why.
347 The rdate utility allows you to synchronize the date and time of your
348 system clock with the date and time of a remote networked system using
349 the RFC868 protocol, which is built into the inetd daemon on most
352 config CONFIG_READPROFILE
356 This allows you to parse /proc/profile for basic profiling.
358 config CONFIG_SWAPONOFF
362 This option enables both the 'swapon' and the 'swapoff' utilities.
363 Once you have created some swap space using 'mkswap', you also need
364 to enable your swap space with the 'swapon' utility. The 'swapoff'
365 utility is used, typically at system shutdown, to disable any swap
366 space. If you are not using any swap space, you can leave this
373 All files and filesystems in Unix are arranged into one big directory
374 tree. The 'mount' utility is used to graft a filesystem onto a
375 particular part of the tree. A filesystem can either live on a block
376 device, or it can be accessible over the network, as is the case with
377 NFS filesystems. Most people using BusyBox will also want to enable
380 config CONFIG_FEATURE_MOUNT_NFS
381 bool " Support mounting NFS file systems"
383 depends on CONFIG_MOUNT
385 Enable mounting of NFS file systems.
391 When you want to remove a mounted filesystem from its current mount point,
392 for example when you are shutting down the system, the 'umount' utility is
393 the tool to use. If you enabled the 'mount' utility, you almost certainly
394 also want to enable 'umount'.
396 comment "Common options for mount/umount"
397 depends on CONFIG_MOUNT || CONFIG_UMOUNT
399 config CONFIG_FEATURE_MOUNT_LOOP
400 bool " Support loopback mounts"
402 depends on CONFIG_MOUNT || CONFIG_UMOUNT
404 Enabling this feature allows automatic mounting of files (containing
405 filesystem images) via the linux kernel's loopback devices. The mount
406 command will detect you are trying to mount a file instead of a block
407 device, and transparently associate the file with a loopback device.
408 The umount command will also free that loopback device.
410 You can still use the 'losetup' utility (to manually associate files
411 with loop devices) if you need to do something advanced, such as
412 specify an offset or cryptographic options to the loopback device.
413 (If you don't want umount to free the loop device, use "umount -D".)
415 config CONFIG_FEATURE_MTAB_SUPPORT
416 bool " Support for the old /etc/mtab file"
418 depends on CONFIG_MOUNT || CONFIG_UMOUNT
420 Historically, Unix systems kept track of the currently mounted
421 partitions in the file "/etc/mtab". These days, the kernel exports
422 the list of currently mounted partitions in "/proc/mounts", rendering
423 the old mtab file obsolete. (In modern systems, /etc/mtab should be
424 a symlink to /proc/mounts.)
426 The only reason to have mount maintain an /etc/mtab file itself is if
427 your stripped-down embedded system does not have a /proc directory.
428 If you must use this, keep in mind it's inherently brittle (for
429 example a mount under chroot won't update it), can't handle modern
430 features like separate per-process filesystem namespaces, requires
431 that your /etc directory be writeable, tends to get easily confused
432 by --bind or --move mounts, and so on. (In brief: avoid.)