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Linux whatis command and definitions of some commands in /bin and /sbin directories

Linux whatis command searches the whatis database for complete words.

See some command descriptions from whatis database:

addpart (8) - simple wrapper around the add partition ioctl

agetty (8) - alternative Linux getty

arch (1) - print machine hardware name (same as uname -m)

arp (7) - Linux ARP kernel module

arp (8) - manipulate the system ARP cache

arping (8) - send ARP REQUEST to a neighbour host

audispd (8) - an event multiplexor

auditctl (8) - a utility to assist controlling the kernel's audit system

auditd (8) - The Linux Audit daemon

aureport (8) - a tool that produces summary reports of audit daemon logs

ausearch (8) - a tool to query audit daemon logs

ausearch-expression (5) - audit search expression format

autrace (8) - a program similar to strace

awk (1p) - pattern scanning and processing language

badblocks (8) - search a device for bad blocks

basename (1p) - return non-directory portion of a pathname

basename (1) - strip directory and suffix from filenames

basename (3) - parse pathname components

basename (3p) - return the last component of a pathname

bash (1) - GNU Bourne-Again SHell

blkdeactivate (8) - utility to deactivate block devices

blkdiscard (8) - discard sectors on a device

blkid (8) - command-line utility to locate/print block device attributes

blockdev (8) - call block device ioctls from the command line

bridge (8) - show / manipulate bridge addresses and devices

cat (1) - concatenate files and print on the standard output

cat (1p) - concatenate and print files

cfdisk (8) - Curses based disk partition table manipulator for Linux

chcpu (8) - configure CPUs

chgrp (1) - change group ownership

chgrp (1p) - change the file group ownership

chkconfig (8) - updates and queries runlevel information for system services

chmod (1) - change file mode bits

chmod (1p) - change the file modes

chmod (2) - change permissions of a file

chmod (3p) - change mode of a file

chown (1) - change file owner and group

chown (1p) - change the file ownership

chown (2) - change ownership of a file

chown (3p) - change owner and group of a file

clock (3) - Determine processor time

clock (3p) - report CPU time used

consoletype (1) - print type of the console connected to standard input

cp (1) - copy files and directories

cp (1p) - copy files

cpio (1) - copy files to and from archives

ctrlaltdel (8) - set the function of the Ctrl-Alt-Del combination

cut (1p) - cut out selected fields of each line of a file

cut (1) - remove sections from each line of files

date (1) - print or set the system date and time

date (1p) - write the date and time

dd (1) - convert and copy a file

dd (1p) - convert and copy a file

debugfs (8) - ext2/ext3/ext4 file system debugger

delpart (8) - simple wrapper around the del partition ioctl

depmod (8) - program to generate modules.dep and map files

df (1p) - report free disk space

df (1) - report file system disk space usage

dhclient (8) - Dynamic Host Configuration Protocol Client

dhclient-script (8) - DHCP client network configuration script

dmesg (1) - print or control the kernel ring buffer

dmeventd (8) - Device-mapper event daemon

dmsetup (8) - low level logical volume management

dracut (8) - create initial ramdisk images for preloading modules

dumpe2fs (8) - dump ext2/ext3/ext4 filesystem information

dumpkeys (1) - dump keyboard translation tables

e2fsck (8) - check a Linux ext2/ext3/ext4 file system

e2image (8) - Save critical ext2/ext3/ext4 filesystem metadata to a file

e2label (8) - Change the label on an ext2/ext3/ext4 filesystem

e2undo (8) - Replay an undo log for an ext2/ext3/ext4 filesystem

echo (1) - display a line of text

echo (1p) - write arguments to standard output

env (1p) - set the environment for command invocation

env (1) - run a program in a modified environment

Env (3pm) - perl module that imports environment variables as scalars or arrays

ether-wake (8) - A tool to send a Wake-On-LAN Magic Packet

ethtool (8) - query or control network driver and hardware settings

ex (1p) - text editor

faillock (8) - Tool for displaying and modifying the authentication failure record files

false (1) - do nothing, unsuccessfully

false (1p) - return false value

fdisk (8) - Partition table manipulator for Linux

find (1p) - find files

find (1) - search for files in a directory hierarchy

findfs (8) - Find a filesystem by label or UUID

findmnt (8) - find a filesystem

fixfiles (8) - fix file SELinux security contexts

fsadm (8) - utility to resize or check filesystem on a device

fsck (8) - check and repair a Linux file system

fsfreeze (8) - suspend access to an filesystem (Linux Ext3/4, ReiserFS, JFS, XFS)

fstab-decode (8) - run a command with fstab-encoded arguments

fstrim (8) - discard unused blocks on a mounted filesystem

fuser (1) - identify processes using files or sockets

fuser (1p) - list process IDs of all processes that have one or more files open

gawk (1) - pattern scanning and processing language

genhostid (1) - generate and set a hostid for the current host

getkey (1) - wait until a key is pressed

grep (1) - print lines matching a pattern

grep (1p) - search a file for a pattern

grub (8) - the grub shell

grubby (8) - command line tool for configuring grub, lilo, and elilo

grub-install (8) - install GRUB on your drive

grub-md5-crypt (8) - Encrypt a password in MD5 format

grub-terminfo (8) - Generate a terminfo command from a terminfo name

gzip (1) - compress or expand files

halt (8) - reboot or stop the system

hostname (1) - show or set the system's host name

hostname (7) - hostname resolution description

hwclock (8) - query and set the hardware clock (RTC)

ifcfg (8) - simplistic script which replaces ifconfig IP managment

ifconfig (8) - configure a network interface

ifdown (8) - take a network interface down

ifenslave (8) - Attach and detach slave network devices to a bonding device

ifup (8) - bring a network interface up

init (5) - Upstart init daemon job configuration

init (8) - Upstart process management daemon

initctl (8) - init daemon control tool

insmod (8) - simple program to insert a module into the Linux Kernel

install-info (1) - update info/dir entries

installkernel (8) - tool to script kernel installation

ip6tables (8) - IPv6 packet filter administration

ip6tables-restore (8) - Restore IPv6 Tables

ip6tables-save (8) - dump iptables rules to stdout

ip (7) - Linux IPv4 protocol implementation

ip (8) - show / manipulate routing, devices, policy routing and tunnels

ipcalc (1) - perform simple manipulation of IP addresses

ipmaddr (8) - adds, deletes, and displays multicast addresses

iptables (8) - administration tool for IPv4 packet filtering and NAT

iptables-restore (8) - Restore IP Tables

iptables-save (8) - dump iptables rules to stdout

iptables-xml (8) - Convert iptables-save format to XML

iptunnel (8) - creates, deletes, and displays configured tunnels

kbd_mode (1) - report or set the keyboard mode

kill (1p) - terminate or signal processes

kill (1) - terminate a process

kill (2) - send signal to a process

kill (3p) - send a signal to a process or a group of processes

killall5 (8) -- send a signal to all processes

link (1) - call the link function to create a link to a file

link (1p) - call link function

link (2) - make a new name for a file

link (3p) - link to a file

ln (1) - make links between files

ln (1p) - link files

loadkeys (1) - load keyboard translation tables

load_policy (8) - load a new SELinux policy into the kernel

logger (1) - a shell command interface to the syslog(3) system log module

logger (1p) - log messages

login (1) - sign on

login (3) - write utmp and wtmp entries

logsave (8) - save the output of a command in a logfile

losetup (8) - set up and control loop devices

ls (1) - list directory contents

ls (1p) - list directory contents

lsblk (8) - list block devices

lsinitrd (1) - tool to show the contents of an initramfs image

lsmod (8) - program to show the status of modules in the Linux Kernel

lspci (8) - list all PCI devices

lvchange (8) - change attributes of a logical volume

lvconvert (8) - convert a logical volume from linear to mirror or snapshot

lvcreate (8) - create a logical volume in an existing volume group

lvdisplay (8) - display attributes of a logical volume

lvextend (8) - extend the size of a logical volume

lvm (8) - LVM2 tools

lvmchange (8) - change attributes of the logical volume manager

lvmconf (8) - LVM configuration modifier

lvmdiskscan (8) - scan for all devices visible to LVM2

lvmdump (8) - create lvm2 information dumps for diagnostic purposes

lvmetad (8) - LVM metadata cache daemon

lvmsadc (8) - LVM system activity data collector

lvmsar (8) - LVM system activity reporter

lvreduce (8) - reduce the size of a logical volume

lvremove (8) - remove a logical volume

lvrename (8) - rename a logical volume

lvresize (8) - resize a logical volume

lvs (8) - report information about logical volumes

lvscan (8) - scan (all disks) for Logical Volumes

makedev (3) - manage a device number

MAKEDEV (8) - create devices

matchpathcon (8) - get the default SELinux security context for the specified path from the file contexts configuration

mii-diag (8) - Network adapter control and monitoring

mii-tool (8) - view, manipulate media-independent interface status

mingetty (8) - minimal getty for consoles

mkdir (1) - make directories

mkdir (1p) - make directories

mkdir (2) - create a directory

mkdir (3p) - make a directory

mke2fs (8) - create an ext2/ext3/ext4 filesystem

mkfs (8) - build a Linux file system

mkhomedir_helper (8) - Helper binary that creates home directories

mkinitrd (8) - is a compat wrapper, which calls dracut to generate an initramfs

mknod (1) - make block or character special files

mknod (2) - create a special or ordinary file

mknod (3p) - make a directory, a special file, or a regular file

mkswap (8) - set up a Linux swap area

mktemp (1) - create a temporary file or directory

mktemp (3) - make a unique temporary filename

mktemp (3p) - make a unique filename (LEGACY)

modinfo (8) - program to show information about a Linux Kernel module

modprobe (8) - program to add and remove modules from the Linux Kernel

more (1) - file perusal filter for crt viewing

more (1p) - display files on a page-by-page basis

mount (2) - mount file system

mount (8) - mount a filesystem

mountpoint (1) - see if a directory is a mountpoint

mv (1) - move (rename) files

mv (1p) - move files

nameif (8) - name network interfaces based on MAC addresses

netreport (1) - request notification of network interface changes

netstat (8) - Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships

nice (1p) - invoke a utility with an altered nice value

nice (1) - run a program with modified scheduling priority

nice (2) - change process priority

nice (3p) - change the nice value of a process

nologin (5) - prevent non-root users from logging into the system

nologin (8) - politely refuse a login

pam_console_apply (8) - set or revoke permissions for users at the system console

pam_tally2 (8) - The login counter (tallying) module

pam_timestamp_check (8) - Check to see if the default timestamp is valid

partx (8) - telling the kernel about presence and numbering of on-disk partitions

pidof (8) -- find the process ID of a running program

ping6 (8) - send ICMP ECHO_REQUEST to network hosts

ping (8) - send ICMP ECHO_REQUEST to network hosts

pivot_root (2) - change the root file system

pivot_root (8) - change the root file system

plipconfig (8) - fine tune PLIP device parameters

plymouth (8) - A graphical boot system and logger

poweroff (8) - reboot or stop the system

ppp-watch (8) - daemon to make PPP interfaces act more like other interfaces

ps (1p) - report process status

ps (1) - report a snapshot of the current processes

pvchange (8) - change attributes of a physical volume

pvck (8) - check physical volume metadata

pvcreate (8) - initialize a disk or partition for use by LVM

pvdisplay (8) - display attributes of a physical volume

pvmove (8) - move physical extents

pvremove (8) - remove a physical volume

pvresize (8) - resize a disk or partition in use by LVM2

pvs (8) - report information about physical volumes

pvscan (8) - scan all disks for physical volumes

pwd (1p) - return working directory name

pwd (1) - print name of current/working directory

quotacheck (8) - scan a filesystem for disk usage, create, check and repair quota files

quotaoff (8) - turn filesystem quotas on and off

quotaon (8) - turn filesystem quotas on and off

raw (7) - Linux IPv4 raw sockets

raw (8) - bind a Linux raw character device

rdisc (8) - network router discovery daemon

readlink (1) - print value of a symbolic link or canonical file name

readlink (2) - read value of a symbolic link

readlink (3p) - read the contents of a symbolic link

reboot (2) - reboot or enable/disable Ctrl-Alt-Del

reboot (8) - reboot or stop the system

resize2fs (8) - ext2/ext3/ext4 file system resizer

restorecon (8) - restore file(s) default SELinux security contexts

rm (1p) - remove directory entries

rm (1) - remove files or directories

rmdir (1p) - remove directories

rmdir (1) - remove empty directories

rmdir (2) - delete a directory

rmdir (3p) - remove a directory

rmmod (8) - simple program to remove a module from the Linux Kernel

route (8) - show / manipulate the IP routing table

rpm (8) - RPM Package Manager

rsyslogd (8) - reliable and extended syslogd

rtmon (8) - listens to and monitors RTnetlink

runlevel (7) - event signalling change of system runlevel

runlevel (8) - output previous and current runlevel

runuser (1) - run a shell with substitute user and group IDs

scsi_id (8) - retrieve and generate a unique SCSI identifier

securetty (5) - file which lists ttys from which root can log in

securetty (8) - add a tty to /etc/securetty

sed (1p) - stream editor

sed (1) - stream editor for filtering and transforming text

service (8) - run a System V init script

setfiles (8) - set file SELinux security contexts

setfont (8) - load EGA/VGA console screen font

setpci (8) - configure PCI devices

setsysfont (8) - set console font according to /etc/sysconfig/i18n

sfdisk (8) - Partition table manipulator for Linux

sh (1p) - shell, the standard command language interpreter

shutdown (2) - shut down part of a full-duplex connection

shutdown (3p) - shut down socket send and receive operations

shutdown (8) - bring the system down

slattach (8) - attach a network interface to a serial line

sleep (1) - delay for a specified amount of time

sleep (1p) - suspend execution for an interval

sleep (3p) - suspend execution for an interval of time

sleep (3) - Sleep for the specified number of seconds

sln (8) - static ln

sort (1p) - sort, merge, or sequence check text files

sort (1) - sort lines of text files

sort (3pm) - perl pragma to control sort() behaviour

stty (1) - change and print terminal line settings

stty (1p) - set the options for a terminal

su (1) - run a shell with substitute user and group IDs

sulogin (8) - Single-user login

sushell (8) - execute the single-user shell

swapon (2) - start/stop swapping to file/device

swapon (8) - enable/disable devices and files for paging and swapping

switch_root (8) - switch to another filesystem as the root of the mount tree

sync (1) - flush file system buffers

sync (2) - commit buffer cache to disk

sync (3p) - schedule file system updates

sync (8) - synchronize data on disk with memory

sysctl (2) - read/write system parameters

sysctl (8) - configure kernel parameters at runtime

taskset (1) - retrieve or set a process's CPU affinity

tc (8) - show / manipulate traffic control settings

telinit (8) - change system runlevel

touch (1) - change file timestamps

touch (1p) - change file access and modification times

tracepath6 (8) - traces path to a network host discovering MTU along this path

tracepath (8) - traces path to a network host discovering MTU along this path

true (1) - do nothing, successfully

true (1p) - return true value

tune2fs (8) - adjust tunable filesystem parameters on ext2/ext3/ext4 filesystems

udevadm (8) - udev management tool

udevd (8) - event managing daemon

umount (2) - unmount file system

umount (8) - unmount file systems

uname (1p) - return system name

uname (1) - print system information

uname (2) - get name and information about current kernel

uname (3p) - get the name of the current system

unicode_start (1) - put keyboard and console in unicode mode

unicode_stop (1) - revert keyboard and console from unicode mode

unix_chkpwd (8) - Helper binary that verifies the password of the current user

unix_update (8) - Helper binary that updates the password of a given user

unlink (1) - call the unlink function to remove the specified file

unlink (1p) - call the unlink function

unlink (2) - delete a name and possibly the file it refers to

unlink (3p) - remove a directory entry

usleep (1) - sleep some number of microseconds

usleep (3p) - suspend execution for an interval

usleep (3) - suspend execution for microsecond intervals

vgcfgbackup (8) - backup volume group descriptor area

vgcfgrestore (8) - restore volume group descriptor area

vgchange (8) - change attributes of a volume group

vgck (8) - check volume group metadata

vgconvert (8) - convert volume group metadata format

vgcreate (8) - create a volume group

vgdisplay (8) - display attributes of volume groups

vgexport (8) - make volume groups unknown to the system

vgextend (8) - add physical volumes to a volume group

vgimport (8) - make exported volume groups known to the system

vgimportclone (8) - import and rename duplicated volume group (e.g. a hardware snapshot)

vgmerge (8) - merge two volume groups

vgmknodes (8) - recreate volume group directory and logical volume special files

vgreduce (8) - reduce a volume group

vgremove (8) - remove a volume group

vgrename (8) - rename a volume group

vgs (8) - report information about volume groups

vgscan (8) - scan all disks for volume groups and rebuild caches

vgsplit (8) - split a volume group into two

vi (1p) - screen-oriented (visual) display editor

wipefs (8) - wipe a filesystem signature from a device

zcat (1p) - expand and concatenate data

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