System query key

SysRq key on a US 102-key keyboard circled in red

The system request shortly SysRq on Swiss and US keyboards SysRq (short for . English System Request ), is a relic of old terminal - keyboards on which the button to reset the keyboard or change from one session to next causes. This function was first introduced as a separate key on PC keyboards in 1984 with the IBM Personal Computer / AT , which increased the number of keys from 83 to 84. After the key was hardly used by software, contrary to expectations, IBM transferred the function to the print key as an additional function in 1987 with the 101/102 key MF2 keyboard ; the system query function now and to date the key combination + or for international keyboards + realized. The system query key, however, still has its own scan code , which does not correspond to that of the print key, and can therefore be on a different key combination or be missing entirely on notebook keyboards. AltDruckAltPrtSc

function

Under Windows from Microsoft (the Druckkey is generally the screenshot directly into the clipboard without an interface ), Alt+ Druck(i.e. the S-Abf assignment of the German / Austrian standard keyboard) is a photo of only the currently active window .

Under Windows you can start the kernel debugger Strgby pressing the key combination and pressing it twice S-Abfafter this function has been activated in the registry . This function is no longer available in Windows 10 .

With newer Linux versions, this key can be configured in such a way that certain actions can still be carried out (e.g. reboot with prior writing of buffered data on the data carrier ) even if the terminal or X server is blocked by a software or hardware error . Only a few parts of the kernel still need to be operational to use this function. This is called the Magic SysRq key (Magic S-Abf key) .

Buttons on a IBM / Windows - Keyboard ( German / Austrian occupation "T1")

Esc

F1

F2

F3

F4

F5

F6

F7

F8

F9

F10

F11

F12

Print S-Dep

roll

pause break

Numeric keypad :

Insert

Pos1

Image ↑

Num

/

*

-

Dist

The End

Image ↓

7th

8th

9

+

4th

5

6th

↑

1

2

3

Enter

←

↓

→

0

,