Linux Commands Reference
https://github.com/coreutils/coreutils
https://man7.org/linux/man-pages/dir_all_alphabetic.html
#sysctl Kernel Parameter (sysctl, procfs) https://www.kernel.org/doc/Documentation/sysctl/kernel.txt
Bash Command Line | Function |
---|---|
A | |
alias | Create an alias |
apropos | Search Help manual pages (man -k) |
apt-get | Search for and install software packages (Debian/Ubuntu) |
aptitude | Search for and install software packages (Debian/Ubuntu) |
aspell | Spell Checker |
awk | Find and Replace text, database sort/validate/index |
B | |
basename | Strip directory and suffix from filenames |
bash | GNU Bourne-Again SHell |
bc | Arbitrary precision calculator language |
bg | Send to background |
break | Exit from a loop |
builtin | Run a shell builtin |
bzip2 | Compress or decompress named file(s) |
C | |
cal | Display a calendar |
case | Conditionally perform a command |
cat | Concatenate and print (display) the content of files |
cd | Change Directory |
cfdisk | Partition table manipulator for Linux |
chgrp | Change group ownership |
chmod | Change access permissions |
chown | Change file owner and group |
chroot | Run a command with a different root directory |
chkconfig | System services (runlevel) |
cksum | Print CRC checksum and byte counts |
clear | Clear terminal screen |
cmp | Compare two files |
comm | Compare two sorted files line by line |
command | Run a command – ignoring shell functions |
continue | Resume the next iteration of a loop |
cp | Copy one or more files to another location |
cron | Daemon to execute scheduled commands |
crontab | Schedule a command to run at a later time |
csplit | Split a file into context-determined pieces |
curl | Transfer data from or to a server |
cut | Divide a file into several parts |
D | |
date | Display or change the date & time |
dc | Desk Calculator |
dd | Convert and copy a file, write disk headers, boot records |
ddrescue | Data recovery tool |
declare | Declare variables and give them attributes |
df | Display free disk space |
diff | Display the differences between two files |
diff3 | Show differences among three files |
dig | DNS lookup |
dir | Briefly list directory contents |
dircolors | Colour setup for `ls’ |
dirname | Convert a full pathname to just a path |
dirs | Display list of remembered directories |
dmesg | Print kernel & driver messages |
du | Estimate file space usage |
E | |
echo | Display message on screen |
egrep | Search file(s) for lines that match an extended expression |
eject | Eject removable media |
enable | Enable and disable builtin shell commands |
env | Environment variables |
ethtool | Ethernet card settings |
eval | Evaluate several commands/arguments |
exec | Execute a command |
exit | Exit the shell |
expect | Automate arbitrary applications accessed over a terminal |
expand | Convert tabs to spaces |
export | Set an environment variable |
expr | Evaluate expressions |
F | |
false | Do nothing, unsuccessfully |
fdformat | Low-level format a floppy disk |
fdisk | Partition table manipulator for Linux |
fg | Send job to foreground |
fgrep | Search file(s) for lines that match a fixed string |
file | Determine file type |
find | Search for files that meet a desired criteria |
fmt | Reformat paragraph text |
fold | Wrap text to fit a specified width |
for | Expand words, and execute commands |
format | Format disks or tapes |
free | Display memory usage |
fsck | File system consistency check and repair |
ftp | File Transfer Protocol |
function | Define Function Macros |
fuser | Identify/kill the process that is accessing a file |
G | |
gawk | Find and Replace text within file(s) |
getopts | Parse positional parameters |
grep | Search file(s) for lines that match a given pattern |
groupadd | Add a user security group |
groupdel | Delete a group |
groupmod | Modify a group |
groups | Print group names a user is in |
gzip | Compress or decompress named file(s) |
H | |
hash | Remember the full pathname of a name argument |
head | Output the first part of file(s) |
help | Display help for a built-in command |
history | Command History |
hostname | Print or set system name |
htop | Interactive process viewer |
I | |
iconv | Convert the character set of a file |
id | Print user and group id’s |
if | Conditionally perform a command |
ifconfig | Configure a network interface |
ifdown | Stop a network interface |
ifup | Start a network interface up |
import | Capture an X server screen and save the image to file |
install | Copy files and set attributes |
ip | Routing, devices and tunnels |
J | |
jobs | List active jobs |
join | Join lines on a common field |
K | |
kill | Kill a process by specifying its PID |
killall | Kill processes by name |
L | |
less | Display output one screen at a time |
let | Perform arithmetic on shell variables |
link | Create a link to a file |
ln | Create a symbolic link to a file |
local | Create variables |
locate | Find files |
logname | Print current login name |
logout | Exit a login shell |
look | Display lines beginning with a given string |
lpc | Line printer control program |
lpr | Off line print |
lprint | Print a file |
lprintd | Abort a print job |
lprintq | List the print queue |
lprm | Remove jobs from the print queue |
ls | List information about file(s) |
lsof | List open files |
M | |
make | Recompile a group of programs |
man | Help manual |
mkdir | Create new folder(s) |
mkfifo | Make FIFOs (named pipes) |
mkisofs | Create an hybrid ISO9660/JOLIET/HFS filesystem |
mknod | Make block or character special files |
more | Display output one screen at a time |
most | Browse or page through a text file |
mount | Mount a file system |
mtools | Manipulate MS-DOS files |
mtr | Network diagnostics (traceroute/ping) |
mv | Move or rename files or directories |
mmv | Mass Move and rename (files) |
N | |
nc | Netcat, read and write data across networks |
netstat | Networking information |
nice | Set the priority of a command or job |
nl | Number lines and write files |
nohup | Run a command immune to hangups |
notify-send | Send desktop notifications |
nslookup | Query Internet name servers interactively |
O | |
open | Open a file in its default application |
op | Operator access |
P | |
passwd | Modify a user password |
paste | Merge lines of files |
pathchk | Check file name portability |
ping | Test a network connection |
pkill | Kill processes by a full or partial name |
popd | Restore the previous value of the current directory |
pr | Prepare files for printing |
printcap | Printer capability database |
printenv | Print environment variables |
printf | Format and print data |
ps | Process status |
pushd | Save and then change the current director |
pv | Monitor the progress of data through a pipe |
pwd | Print Working Directory |
Q | |
quota | Display disk usage and limits |
quotacheck | Scan a file system for disk usag |
R | |
ram | ram disk device |
rar | Archive files with compression |
rcp | Copy files between two machines |
read | Read a line from standard input |
readarray | Read from stdin into an array variable |
readonly | Mark variables/functions as readonly |
reboot | Reboot the system |
rename | Rename files |
renice | Alter priority of running processes |
return | Exit a shell function |
rev | Reverse lines of a file |
rm | Remove files |
rmdir | Remove folder(s) |
rsync | Remote file copy (Synchronize file trees) |
S | |
screen | Multiplex terminal, run remote shells via ssh |
scp | Secure copy (remote file copy) |
sdiff | Merge two files interactively |
sed | Stream Editor |
select | Accept keyboard input |
seq | Print numeric sequences |
set | Manipulate shell variables and functions |
sftp | Secure File Transfer Program |
shift | Shift positional parameters |
shopt | Shell Options |
shutdown | Shutdown or restart linux |
sleep | Delay for a specified time |
slocate | Find files |
sort | Sort text files |
source | Run commands from a file ‘.’ |
split | Split a file into fixed-size pieces |
ssh | Secure Shell client (remote login program) |
stat | Display file or file system status |
strace | Trace system calls and signals |
su | Substitute user identity |
sudo | Execute a command as another user |
sum | Print a checksum for a file |
suspend | Suspend execution of this shell |
sync | Synchronize data on disk with memory |
T | |
tail | Output the last part of file |
tar | Store, list or extract files in an archive |
tee | Redirect output to multiple files |
test | Evaluate a conditional expression |
time | Measure Program running time |
timeout | Run a command with a time limit |
times | User and system times |
touch | Change file timestamps |
top | List processes running on the system |
tput | Set terminal-dependent capabilities, color, position |
traceroute | Trace Route to Host |
trap | Run a command when a signal is set(bourne) |
tr | Translate, squeeze, and/or delete characters |
TRUE | Do nothing, successfully |
tsort | Topological sort |
tty | Print filename of terminal on stdin |
type | Describe a command |
U | |
ulimit | Limit user resources |
umask | Users file creation mask |
umount | Unmount a device |
unalias | Remove an alias |
uname | Print system information |
unexpand | Convert spaces to tabs |
uniq | Uniquify files |
units | Convert units from one scale to another |
unrar | Extract files from a rar archive |
unset | Remove variable or function names |
unshar | Unpack shell archive scripts |
until | Execute commands (until error) |
uptime | Show uptime |
useradd | Create new user account |
userdel | Delete a user account |
usermod | Modify user account |
users | List users currently logged in |
uuencode | Encode a binary file |
uudecode | Decode a file created by uuencode |
V | |
v | Verbosely list directory contents (`ls -l -b’) |
vdir | Verbosely list directory contents (`ls -l -b’) |
vi | Text Editor |
vmstat | Report virtual memory statistics |
W | |
wait | Wait for a process to complete |
watch | Execute/display a program periodically |
wc | Print byte, word, and line counts |
whereis | Search the user’s $path, man pages and source files for a program |
which | Search the user’s $path for a program file |
while | Execute commands |
who | Print all usernames currently logged in |
whoami | Print the current user id and name (`id -un’) |
wget | Retrieve web pages or files via HTTP, HTTPS or FTP |
write | Send a message to another user |
X | |
xargs | Execute utility, passing constructed argument list(s) |
xdg-open | Open a file or URL in the user’s preferred application |
xz | Compress or decompress .xz and .lzma files |
Y | |
yes | Print a string until interrupted |
Z | |
zip | Package and compress (archive) files |
Special Characters | |
. | Run a command script in the current shell |
!! | Run the last command again |
### | Comment / Remark |