Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

On my keyboard, the key the functions as the Print Screen key when the F-lock is on has "SysRq" below it (presumably to be used when F-lock is off). What is it and what does it do?

share|improve this question
1  
There is a Wikipedia page for the System Request key. –  nik Jul 16 '09 at 2:46
1  
Any chance of choosing a correct answer? The question is almost 4 1/2 years old and answer pending for over 2 years. Thanks –  Dominic Zukiewicz Oct 9 '14 at 7:55
    
Any chance of choosing a correct answer? The question is almost 4 1/2 years old and answer pending for over 2 years. –  Nifle Feb 10 at 17:36

2 Answers 2

SysRq was introduced on IBM PC keyboards as a way to have a cross-platform way to initiate a low-level event. When typing the keys, they get put into a buffer and flushed periodically. If your machine locks up, the keyboard does not work.

The SysRq key was basically to force a command to be sent to the computer, bypassing the buffer, to trigger a low level call; usually a RESET event.

However, each OS ignores this key now, and uses a preferred combination keystroke to initiate some sort of 'Task Manager' like interface enabling the OS to remain running, rather than a reset the computer.

Its much more common to run applications from the host OS, rather than from the BIOS. It wasn't like that in the 1980's :-)

share|improve this answer

It is a programmable key which can be made to do a variety of things, depends.

I remember it having some uses on old ibm terminals, and some DOS programs used it for a form of soft resetting.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.