Linux Keyboard_shortcuts

Standard shortcuts

Kernel

There are several low level shortcuts that are implemented in the kernel which can be used for debugging and recovering from an unresponsive system. Whenever possible, it is recommended that you use these shortcuts instead of doing a hard shutdown (holding down the power button to completely power off the system).

To use these, they must first be activated with either sysctl kernel.sysrq=1 or echo "1" > /proc/sys/kernel/sysrq. If you wish to have it enabled during boot, edit /etc/sysctl.d/99-sysctl.conf and insert the text kernel.sysrq = 1. If you want to make sure it will be enabled even before the partitions are mounted and in the initrd, then add sysrq_always_enabled=1 to your kernel parameters.

A common idiom to remember this is "Reboot Even If System Utterly Broken" (also referred to as "REISUB"). Alternatively, think of it as "BUSIER" backwards.

Keyboard Shortcut	Description
Alt+SysRq+r Unraw	Take control of keyboard back from X.
Alt+SysRq+e Terminate	Send SIGTERM to all processes, allowing them to terminate gracefully.
Alt+SysRq+i Kill	Send SIGKILL to all processes, forcing them to terminate immediately.
Alt+SysRq+s Sync	Flush data to disk.
Alt+SysRq+u Unmount	Unmount and remount all filesystems read-only.
Alt+SysRq+b Reboot	Reboot

Tip:

• If you are using a display manager and after Alt+SysRq+e you are presented with the login screen (or full desktop if autologin is enabled), it is most likely caused by Restart=always directive in the relevant service file. If necessary, edit the unit, however this should not prevent the "REISUB" sequence from working.
• If all the above combinations work except Alt+SysRq+b, try using the contralateral Alt key.
• On laptops that use Fn key to differentiate SysRq from PrtScrn, it may not actually be necessary to use the Fn key (i.e., Alt+PrtSc+letter could work).
• On Lenovo laptops SysRq is often configured as Fn+S. To use it press and hold Alt then press Fn+s, release Fn and s still holding Alt followed by the keys above.
• You may need to press Ctrl along with Alt. So for example, full key shortcut would be Ctrl+Alt+SysRq+b.

See Wikipedia:Magic SysRq key for more details.

Terminal

Virtual console

See Wikipedia:Virtual console

Keyboard Shortcut	Description
Ctrl+Alt+Del	Reboots Computer (specified by the symlink /usr/lib/systemd/system/ctrl-alt-del.target)
Alt+F1, F2, F3, ...	Switch to n-th virtual console
Alt+ ←	Switch to previous virtual console
Alt+ →	Switch to next virtual console
Scroll Lock	When Scroll Lock is activated, input/output is locked
Shift+PgUp/PgDown	Scrolls console buffer up/down
Ctrl+c	Kills current task
Ctrl+d	Inserts an EOF
Ctrl+z	Pauses current Task

Readline

GNU readline is a commonly used library for line-editing; it is used for example by Bash, FTP, and many more (see the details of readline package under "Required By" for more examples). readline is also customizable (see man page for details).

Keyboard Shortcut	Description
Ctrl+l	Clear the screen
Cursor Movement
Ctrl+b	Move cursor one character to the left
Ctrl+f	Move cursor one character to the right
Alt+b	Move cursor one word to the left
Alt+f	Move cursor one word to the right
Ctrl+a	Move cursor to start of the line
Ctrl+e	Move cursor to end of the line
Copy & Paste
Ctrl+u	Cut everything from line start to cursor
Ctrl+k	Cut everything from the cursor to end of the line
Alt+d	Cut the current word after the cursor
Ctrl+w	Cut the current word before the cursor
Ctrl+y	Paste the previous cut text
Alt+y	Paste the second latest cut text
Alt+Ctrl+y	Paste the first argument of the previous command
Alt+./_	Paste the last argument of the previous command
History
Ctrl+p	Move to the previous line
Ctrl+n	Move to the next line
Ctrl+s	Search
Ctrl+r	Reverse search
Ctrl+j	End search
Ctrl+g	Abort search (restores original line)
Alt+r	Restores all changes made to line
Completion
Tab	Auto-complete a name
Alt+?	List all possible completions
Alt+*	Insert all possible completions

X11 & Wayland

Keyboard Shortcut	Description	Notes
Ctrl+Alt+F1, F2, F3, ...	Switch to n-th virtual console	If it does not work, try Ctrl+Fn+Alt+F….
Shift+Insert  Mouse Button 2	Paste text from the PRIMARY buffer	By default, Qt maps Shift+Insert to CLIPBOARD instead of the PRIMARY buffer (see e.g. [1]) and Ctrl+Shift+Insert is mapped to the PRIMARY buffer.

More reference: https://wiki.archlinux.org/index.php/Keyboard_shortcuts