Command Line Cheat Sheet

Browsing Access Rights Help Disk Usage Session Utilities Network Utilities Archiving Executable

Browsing

ls

ls [-lh] [DIR]:List file and directories
$ ls
file1       file2   proj1   proj2

$ ls -lh
-rw-r--r--  1 user   group     0B  4 oct 14:11 file1
-rw-r--r--  1 user   group     0B  4 oct 14:11 file2
drwxr-xr-x  2 user   group    64B  4 oct 14:11 proj1
drwxr-xr-x  2 user   group    64B  4 oct 14:11 proj2

$ ls -lh proj1
-rw-r--r--  1 user   group     0B  4 oct 14:14 proj1_file1
-rw-r--r--  1 user   group     0B  4 oct 14:14 proj1_file2

cd

cd DIR:Change current location to a directory
$ ls
file1       file2   proj1   proj2
$ cd proj1
$ ls
proj1_file1 proj1_file2

cp

cp SRC DEST:Copy a file or directory.
cp -Rt DIR SRC...:
 Copy files and/or directories to a directory.

mv

mv SRC DEST:Move or rename a file or directory.
mv -t DIR SRC...:
 Move files and/or directories to a directory.

Tab Key

Tab key:Auto-complete the text
$ cd p[tab]
proj1/ proj2/
$ cd proj

Access Rights

chmod

chmod MODE[,MODE] FILE:
 Set the file mode bits

MODE format

The format of MODE is {ugo}{+-}perms[,...], where perms is one or more letters from the set rwxX

u:set user mode bits
g:set group mode bits
o:set other mode bits
+-:add/remove mode bits
r:read bit
w:write bit
x:execute bit
X:execute bit if already set or if the target is a directory

setfacl

setfacl {--set[-file]|--modify[-file]} MODE {DIR|FILE}:
 Set (purge previous acl permissions) or modify file access control lists. --set[-file] requires permissions of user, group and other to be listed.

MODE format

The format of MODE is u::perms,g::perms,o::perms[,...], where perms is one or more letters from the set rwxX

[u:]uid:perms
Set user mode bits where perms is one or more letters from the set rwxX
[g:]gid:perms
Set group mode bits where perms is one or more letters from the set rwxX
o:perms
Set other mode bits where perms is one or more letters from the set rwxX
r:read bit
w:write bit
x:execute bit
X:execute bit if already set or if the target is a directory
$ setfacl --set u::rwx,g::-,o::-,g:groupid:rwx dir/
$ getfacl dir/
# file: dir/
# owner: ownerid
# group: groupid
user::rwx
group::---
group:groupid:rwx
mask::rwx
other::---

Help

man

Open the help manual (man page) of a command. Not all commands have a man page entry.

man COMMAND:

Open the help manual (man page) of a command.

The manual will be shown in a pager.

$ `man ls
LS(1)                     BSD General Commands Manual                    LS(1)

NAME
     ls -- list directory contents

SYNOPSIS
     ls [-ABCFGHLOPRSTUW@abcdefghiklmnopqrstuwx1] [file ...]

DESCRIPTION
     For each operand that names a file of a type other than directory, ls displays its name as
     well as any requested, associated information.  For each operand that names a file of type
     directory, ls displays the names of files contained within that directory, as well as any
     requested, associated information.
[...]

-h | --help

Display help for a command. The information will be printed in the console.

command -h|--help:
 
Display help for a command.
Commands might have either or both options ( -h , --help ).
$ ls --help
Usage: ls [OPTION]... [FILE]...
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort is specified.

Mandatory arguments to long options are mandatory for short options too.
  -a, --all                  do not ignore entries starting with .
[...]

less

less:Useful to scroll text in a pager rather than print it in the console
$ ls --help | less
Usage: ls [OPTION]... [FILE]...
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort is specified.

Mandatory arguments to long options are mandatory for short options too.
  -a, --all                  do not ignore entries starting with .
[...]

Disk Usage

du

du -sh [DIR]:Print the disk usage of a directory
$ du -sh proj1
1.5K        proj1

Session Utilities

tmux

Enables a number of terminals to be created, accessed, and controlled from a single screen.

tmux:Open a new window
tmux ls|list:List sessions
tmux attach:Attach to the last detached window
tmux attach -t SESSION_INDEX:
 Attach to a detached session

Inside a tmux terminal

Sessions
<Ctrl+b>+s:List sessions
<Ctrl+b>+$:Rename current session
Windows
<Ctrl+b>+w:List all windows
<Ctrl+b>+c:Create a new window
<Ctrl+b>+d:Detach the current window
<Ctrl+b>+,:Rename current window
Panes
<Ctrl+b>+%:Opens a new pane
<Ctrl+b>+Left, Right:
 Change to the left or right pane
<Ctrl+b>+x:Closes the current pane

nohup

nohup COMMAND &:
 Run a command that will NOt HangUP when the terminal closes

Ctrl+C

Ctrl+C:Interrupt the current command

Ctrl+Z

Ctrl+Z:Stop (pause) and background the current command

jobs

jobs:List the background jobs
$ jobs
[1]-  Stopped                 command1
[2]+  Stopped                 command2

fg

fg:Resume the job that’s next in the queue

bg

bg:Push the next job in the queue into the background

ps

ps -fju $USER --forest:
 Display the user’s process tree
UID        PID  PPID  PGID   SID  C STIME TTY          TIME CMD
user     26468 25983 25983 25983  0 10:20 ?        00:00:00 sshd: user@pts/0
user     26591 26468 26591 26591  0 10:20 pts/0    00:00:00  \_ -bash
user     32650 26591 32650 26591  0 10:44 pts/0    00:00:00      \_ ps -fju user --forest

kill

kill %JOB_INDEX:
 Kill a job using the job’s index
kill PID:Kill a process using the process’s id
kill -- -PGID:Kill all process belonging to the process group id
$ kill %1
[1]+  Stopped                 command1

Network Utilities

rsync

rsync -arLv SRC [SRC ...] DEST:
 Recursively copy from source to destination, locally or remotely

Additional Options

--partial Keep partially transferred files
--relative

Copy “implied directories” as well as the last part of SRC. Ex.: foo/bar/ in:

rsync -arLv --relative /foo/bar/baz.c ...

Inserting a ./ in a SRC path will limit the amount of path information that is sent as implied directories. Ex.: bar/ in:

rsync -arLv --relative /foo/./bar/baz.c ...

--bwlimit=RATE

specify the maximum transfer rate for the data sent over the socket, specified in units per second. Ex.: 10 megabytes/sec bandwidth:

rsync -arLv --bwlimit=10mb REMOTE:/foo/ foo/

rsync -arLv --bwlimit=10mb foo/ REMOTE:/foo/

-e <”ssh -p PORT”>
 Use a non-standard SSH port

Archiving

tar

tar -cvf TAR_NAME.tar DIR...:
 Create a .tar archive with the content of directories
tar -czvf TAR_NAME.tar.gz DIR...:
 Create a .tar archive and compress it using gzip
tar -xf TAR_NAME.tar -C DIR:
 Extract a .tar archive into a directory
tar -xzf TAR_NAME.tar.gz -C DIR:
 Extract a .tar archive compressed with gzip into a directory

Additional Options

-r Append files to the .tar archive. This replaces -c.
--sort=name Sort the directory entries on name.

Executable

chmod (execute bit)

chmod +x script.sh:
 Add the execute mode bit to a script file so it can be executed

Execute Script

./script.sh:Execute a script