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Input Devices

Does Your PC Really Need a SysRq Button Anymore? 806

An anonymous reader writes "Ever wondered what the SysRq key on your keyboard does? Lenovo has decided it's so rarely used that it has started removing the key from some new Thinkpad Edge laptops. We already know that Lenovo are something of the fastidious scientists when it comes to keyboard design. Last time they fiddled with the age-old key layout, it was after painstaking research to count exactly how many times users press the Delete and Escape keys. Now it seems another relic of computer keyboards is starting to disappear."
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Does Your PC Really Need a SysRq Button Anymore?

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  • by ls671 ( 1122017 ) * on Thursday January 14, 2010 @11:00AM (#30764112) Homepage

    I don't recall ever using that key although I have coded my own "terminate and stay resident" (TSR) programs back then in order to achieve some level of multitasking in DOS.

    With TSR programs, you could intercept the timer interrupt and do some amount of computation in the background before returning to the running program. You could also intercept the keyboard interrupt in order to switch from one application to another on the fly but I have never actually intercepted the Sysrq key. I used some other hot key combination definition. Maybe back then I though that it wasn't a good idea to fool around with that key but this page says other TSR programmers were using it: []

  • Debug key (Score:5, Interesting)

    by sopssa ( 1498795 ) * <> on Thursday January 14, 2010 @11:01AM (#30764134) Journal

    Ever wondered what the SysRq key on your keyboard does?

    Introduced by IBM with the PC/AT, it was intended to be available as a special key to directly invoke low-level operating system functions with no possibility of conflicting with any existing software.

    In Linux, the kernel can be configured to provide functions for system debugging and crash recovery.[4] This use is known as the "Magic SysRq key".

    Microsoft has used SysRq for various OS- and application-level debuggers. In the CodeView debugger, it was sometimes used to break into the debugging during program execution.[5] For the Windows NT remote kernel debugger, it can be used to force the system into the debugger.[6]

    So it's a handy debugger key for those who need one, functioning in the same key as print screen, but you need to hold alt key. What's the harm having it there, since it already is? It's not like it's an extra button on your keyboard.

    • So it's a handy debugger key for those who need one, functioning in the same key as print screen, but you need to hold alt key. What's the harm having it there, since it already is?

      Because they're probably remapping print screen too. Notice how "print screen" doesn't cause ink to get committed to paper in either Windows or GNOME.

    • by Infiniti2000 ( 1720222 ) on Thursday January 14, 2010 @11:09AM (#30764270)
      Lenovo doesn't need to do any debugging so the key is superfluous to them.
    • Re:Debug key (Score:4, Interesting)

      by houstonbofh ( 602064 ) on Thursday January 14, 2010 @11:14AM (#30764356)

      In Linux, the kernel can be configured to provide functions for system debugging and crash recovery.[4] This use is known as the "Magic SysRq key".

      I guess there will be no more Raising Skinny Elephants on a Lenovo anymore. And while I have only used it a few times in the last year, I have used it.

      • Re:Debug key (Score:5, Informative)

        by ais523 ( 1172701 ) <ais523(524\)(525)x)> on Thursday January 14, 2010 @11:28AM (#30764654)
        This conflicts badly with Ubuntu's decision to make Alt-Sysrq+K the default way to kill X (as opposed to control-alt-backspace which is too easy to press by mistake), too.
        • Re:Debug key (Score:5, Informative)

          by thebasicsteve ( 1672196 ) on Thursday January 14, 2010 @12:51PM (#30766196)
          Ubuntu didn't change the key. On any kernel with the "magic SysRq key" enabled (which Ubuntu has), Alt+SysRq+K kills all running processes on the current VT. Therefore, it kills X.
          Ubuntu's recent decision to disable Ctrl+Alt+Backspace by default is a separate issue.
          On older versions of Ubuntu, you will find that either key combo will kill X.
          • Re: (Score:3, Informative)

            by marcansoft ( 727665 )

            Ubuntu's recent decision to disable Ctrl+Alt+Backspace by default is a separate issue.

            It wasn't Ubuntu's decision, it was Xorg's. I had to explicitly map Ctrl+Alt+Backspace again under Gentoo after a recent Xorg update.

        • Re: (Score:3, Insightful)

          by PitaBred ( 632671 )

          ...too easy to hit by mistake? I have never, ever even come close to hitting ctrl+alt+bksp by mistake. I mean... how would you actually go about doing that?

        • Re:Debug key (Score:4, Informative)

          by colin_s_guthrie ( 929758 ) on Thursday January 14, 2010 @01:58PM (#30767382) Homepage

          I think you're confused. Alt+SysRq+K is one of the Linux "Magic Keys" [] it kills all processes on the current VT, not just X. Most modern X implementations will still work with Ctrl+Alt+BkSp but you now need to do it twice and the first time it makes a rather ominous "beeeeeeeeeep" at you to warn you that you maybe about to make a bad decision....

          So this is hardly an "Ubuntu decision" (like most distros they just package up what's already there, mix it up with a few good and a few bad ideas of their own and paint it nicely).

    • Re:Debug key (Score:4, Informative)

      by digitalhermit ( 113459 ) on Thursday January 14, 2010 @11:21AM (#30764492) Homepage

      Oh heck, I use the SysRq key on an almost daily basis whenever I screw up a kernel compile (and that's often). At least on my keyboards, it's on the same key as PrntScrn. Looking at my keyboard, there's nothing that I don't use on a fairly regular basis:Num Lk - *almost* always on when using a laptop. Almost always off when using a regular keyboard. Pause/Break I've mapped to bring up my task manager. I've also noticed that the paint is actually wearing off the hjkl keys on one keyboard (too much vi).

    • Re: (Score:3, Insightful)

      by mcgrew ( 92797 ) *

      It's just like every other key on your keyboard -- what it does is up to the programmer. Why do OSes use alt-tab to switch between applications, when SysReq is a logical choice? Why did they add that stuupid "windows key" when, again, SysReq would serve perfectly adequately?

      I'd posit that Scroll Lock has been the useless key ever since they started putting the numeric keypad separate from the navigation keys. I always fond it maddening that Bios manufacturers and Microsoft had the numeric keypad set to "cur

  • On my (and I do believe most) keyboards it doubles as a Print Screen button, which I use regularly.
  • Terminals? (Score:4, Informative)

    by russotto ( 537200 ) on Thursday January 14, 2010 @11:04AM (#30764164) Journal

    I'm pretty sure SysRq is a left over from the terminal days, though I don't recall which terminal (the VT100 doesn't have it). It was basically the equivalent of CTRL-ALT-DEL.

    Ahh, Wiki to the rescue; it was from the IBM 3270.

  • Caps Lock
    Num Lock

    Both of these keys should die a firey death before you get rid of the SysRq key, which is very useful for Linux users.

  • by shoppa ( 464619 ) on Thursday January 14, 2010 @11:04AM (#30764180)

    When I learned to type we didn't have these extra "one" and "zero" keys. We used lower case "ell" and upper case "Oh" and we were happy, dang it!

    • Funny? Who modded this funny? Young'uns don't remember, I know, but you have NO idea how many programs barfed in the early days because you got people who couldn't tell the difference between a 0 and an O. So programmers came up with the bright idea to mark the 0 with a dash through it.

      In came the Danes and promptly managed to confuse it with an Ø. We just couldn't win.

      • by hpa ( 7948 )

        The tradition of putting a slash through a zero to distinguish it from O is much older than computers... it was standard operating procedure for Morse telegraphists when writing by hand.

        • Re: (Score:3, Funny)

          by dzfoo ( 772245 )

          Haha! That's silly! Why would they confuse the O with a zero when they write morse code, do they spell out the "DØT"?


    • by FromellaSlob ( 813394 ) on Thursday January 14, 2010 @11:52AM (#30765118)

      Pah. One and zero are the only keys that *are* essential.

    • Re: (Score:3, Funny)

      And '!' was typed as period-backspace-apostrophe (or the reverse). I wonder if I have that thing any more. It was good at making regular marks on paper during a power failure, but it had this extremely bad habit of inserting the character I typed rather than the one I wanted.

  • by TrisexualPuppy ( 976893 ) on Thursday January 14, 2010 @11:04AM (#30764182)
    On my laptop, I use it to toggle VMs. It's perfect because on my machine, it does absolutely nothing. Double scroll lock is the next best bet for me, but my keyboard requires me to press the Fn key simultaneously.

    Is Lenovo leaving any "useless" keys? Some of us actually NEED keys that are otherwise never used and the OSes recognize by default.
    • by Blakey Rat ( 99501 ) on Thursday January 14, 2010 @11:47AM (#30765008)

      IMO, the perfect keyboard was the Mac Classic one, before they made it all PC-compatible.

      My favorite feature was that "Enter" and "Return" were two different keys, so you didn't have to do that retarded "use control-Enter to actually do return" crap that we do all the time now. ("Return" added a new line and "Enter" entered information.)

      "Home" and "End" worked in a reasonable fashion. And "Caps Lock" actually did what the key SAID it did, instead of caps reverse, which is what PCs have always done.

      If I ran the world, I'd get rid of every key that causes more tech support calls than it saves time. This includes "Scroll Lock" and "Pause", which basically work as a "my Excel is broken!" key. And ditto "Insert", except that one's more of a "my Word is broken!" key. Oh, and "Num Lock"... why would anybody ever want the keypad to *not* be a keypad? Definitely scrap that one too.

      And while we're at it, we need Microsoft to make up its mind whether the "Windows" key is a key or a modifier... right now it does both, which is insane.

  • "You can have my SysRq key when you pry it from my cold dead ThinkPad!"

  • by Aldenissin ( 976329 ) on Thursday January 14, 2010 @11:05AM (#30764196)

    I use the "busier" backwards or "reisub" combination with the sysrq key in order to gently shutdown Ubuntu when it locks up. So yes, I use it, but that has only been in the last couple of years or so. Not sure what else it is used for...

  • by djsmiley ( 752149 ) <> on Thursday January 14, 2010 @11:06AM (#30764204) Homepage Journal

    randomly I noticed that key earlier today, because some people have been given new usb keyboards instead of PS2 and they dont have that key (hp keyboards).... and now it appears here...


  • I also notice the Scroll Lock and Pause/Break keys are missing. I know you can use the Scroll Lock key in conjunction with Excel, but I'm not sure anyone else ever does. Although I have actually used it on the command line to, shock and awe, lock the screen from scrolling while it was booting up so I could see error messages before they disappeared into the dust.

    Also, switching the F keys with the functionality usually relegated to Fn-F*, as mentioned in TFA, is nothing new. Apple has been doing that on the

  • I've used it (Score:5, Informative)

    by jonbryce ( 703250 ) on Thursday January 14, 2010 @11:06AM (#30764218) Homepage

    If linux freezes, then Alt-SysRq-S+U+B will do an emergency sync of the disks, unmount them and reboot the system.

    • by mm_202 ( 1569029 ) on Thursday January 14, 2010 @11:12AM (#30764314) Homepage
      Yep... just confirmed that it also works even if Linux isnt frozen...
    • by discord5 ( 798235 ) on Thursday January 14, 2010 @11:18AM (#30764430)

      If linux freezes, then Alt-SysRq-S+U+B will do an emergency sync of the disks, unmount them and reboot the system.

      Bah! That almost looks like an emacs keycombo. M-x-Ctrl-v-p-o-k-l-m-z-w and then press your spacebar with your nose, and it'll do the same thing by the way. It's really handy to have such a shortcut, but the odds of your cat walking over the keyboard and hitting that particular combo are pretty high.

      • Re: (Score:3, Funny)

        by SQL Error ( 16383 )

        Hold down both shift keys, both alt keys, and F1, pop the disk out of the drive and put it back in.

  • Print Screen (Score:5, Insightful)

    by Lord Lode ( 1290856 ) on Thursday January 14, 2010 @11:07AM (#30764240)

    That is the Print Screen key. Don't ever remove that key from the keyboard! I don't care that the word "SysRq" is written below "Print Screen" on that key. Feel free to remove that "SysRq" word from there, but do NOT remove the handy print screen key! Thanks.

    • by jollyreaper ( 513215 ) on Thursday January 14, 2010 @11:14AM (#30764346)

      That is the Print Screen key. Don't ever remove that key from the keyboard! I don't care that the word "SysRq" is written below "Print Screen" on that key. Feel free to remove that "SysRq" word from there, but do NOT remove the handy print screen key! Thanks.

      But if we drop the sysrq key we'll finally have room for the any key.

      • Re: (Score:3, Funny)

        by SharpFang ( 651121 )

        But how will a psychiatrist diagnose their patient then?
        They just need to ask the user to press any key...

        space bar - penile size complex.
        ctrl - control freak
        esc - escapism
        alt - schizophrenia
        shift - split personality
        enter - vaginal fixation
        F1 - overgrown ambition.
        num enter - anal fixation
        num zero - low self esteem
        menu key - bulimic
        tab - drunkard
        backslash - paranoia
        caps lock - Tourette's
        delete - destructive
        arrow up - mania
        arrow down - depression
        windows key - suicidal tendencies
        reset - hopeless idiot.

    • Re:Print Screen (Score:4, Informative)

      by Jaruzel ( 804522 ) on Thursday January 14, 2010 @11:20AM (#30764476) Homepage Journal

      Ditto. Alt+PrtScn is your current-dialog-capturing-friend!

      Although, it still amazes me the amount of people who still install 'freeware' utilities to take screengrabs of dialogs, when Windows has had that functionality built in for many versions... ... and I kid you not, I did once have this conversation:

      User: I need Photoshop CS2 installed, here's my Cost-Code.
      Me: Why?
      User: I write documentation that needs screenshots.
      Me: You know you can screengrab via windows and paste directly into Word?
      User: I don't care, Bob has Photoshop, and I want a copy as well.
      Me: *sigh* Ok, I'll buy a copy and charge your dept...


      • Re: (Score:3, Informative)

        by JediTrainer ( 314273 )
        I don't even bother with that anymore. If you have it, OneNote puts a better screengrabber into Windowkey+S which lets you select the part of the screen that you want to capture (no more cropping!)

        I managed to get that part of OneNote working on Ubuntu as well, although through the tray icon instead of the hotkey. Unfortunately most everything else that I need in OneNote remains broken under the version of CrossOver I have.
  • Windows Key, Esc, CTRL, Alt, Delete, Page up/down, print screen - i use these all the time.
    Home/End/Scroll lock/Insert (annoying)/ Page break (only for dos type screens)/ num lock I either don't use or rarely use.
  • Say what? (Score:3, Funny)

    by djupedal ( 584558 ) on Thursday January 14, 2010 @11:13AM (#30764330)
    "Ever wondered what the SysRq key on your keyboard does?"

    No - since I own a insensitive bork........
    • Re: (Score:3, Informative)

      by noidentity ( 188756 )

      No - since I own a insensitive bork........

      Then you have the Programmer's Key [], though it was removed from Mac designs around 1995, replaced with the Command-Power combination, or on later Macs with USB keyboards, Command-Eject.

  • by WinterSolstice ( 223271 ) on Thursday January 14, 2010 @11:13AM (#30764338)

    I keep seeing these, and I wonder how long it will be until we have nothing but a blackberry style keyboard.

    I guess I can't complain since I still use my Model M and LK463 keyboards, but laptops are getting to the point that the function keys are all remapped to random tasks (brightness, volume, etc) and we keep seeing random multi-media keys... yet stuff like num lock, scroll lock, print screen, break is getting pulled.

    Maybe most suits don't spend anytime dealing with text? Powerpoint doesn't recognize break?

  • by Xest ( 935314 ) on Thursday January 14, 2010 @11:14AM (#30764348)

    Reading through the discussion I looked down to remind myself where on my keyboard it was, only to find that my Logitech keyboard I've been using at work for the last 2 years doesn't even have a Syr rq key.

    My work laptop does though as an alternative on the delete key.

    Still, I didn't even realised it'd gone from my main keyboard!!

  • by darthflo ( 1095225 ) * on Thursday January 14, 2010 @11:16AM (#30764398)

    If this change is indicative of what'll happen to the "serious business" series (T, X, R), then the ThinkPad has, after some 18 years or so, finally jumped the shark.

    One of the main selling points of a ThinkPad was the keyboard. When all the other brands went completely nuts and placed the PrtSc/ScrLk/Pause/Insert/Delete/Home/End/PgUp and PgDn keys at a whim, on a ThinkPad you could blindly hit the spot where the key was supposed to be and actually hit it. They were quite [] proud [] of that, and nobody minded.
    Now, you get a chiclet keyboard with the F-keys disabled by default and six rows. Well, congrats Lenovo, you've just went from top-of-the-line in 2010 to consumer-grade-sony-vaio in 1999 or so.

    Another thing were the displays. Great, high-resolution, matte 4:3 screens one could work with. I own a 12" X61 with 1050 horizontal lines. Nowadays, it's WXGA with less than 800 lines in everything up to 14.1", and half of the models come in glare-type finish. Thanks to the shiny finish you can't see the screen contents anyways, so that slightly mitigates the lack of resolution.

    What's next, Lenovo? Get rid of the high-quality finish of the Notebooks and switch to cheap plastic? Fuck up the support infrastructure IBM built? Oh wait, already happened. I guess it's down to the nipple mouse as the last true hallmark of a ThinkPad. And that, I won't give up 'til you pry it from my cold, dead hands.

    • by Chalex ( 71702 ) on Thursday January 14, 2010 @12:43PM (#30766070) Homepage

      The laptops that are getting this change are the Thinkpad Edge models. They are the low-end consumer level Lenovo laptops, Thinkpads in name only. They are not the regular Thinkpad T or X or R series models. The R series is discontinued now anyway. The regular T and X series are staying as they were (with minor modifications). You can read more details here:

      I look forward to the Thinkpad T series being the solid black square tanks that they have always been.

  • by hey! ( 33014 ) on Thursday January 14, 2010 @11:20AM (#30764464) Homepage Journal

    that the user is pressing the SysRq key.

    In fact, to *urgently* tell the OS that the SysRq. It's not supposed to be buffered or anything, it supposed to grab the OS by the collar and scream "THE USER JUST PRESSED THE DAMMNED SYSRQ KEY!!!!" at it.

    But what is that supposed to mean?

    It doesn't mean anything.

    That's the whole point.

    When they were designing the keyboard, they thought of all the things that you might want a keyboard to say ("STOP SCROLLING", "Show me that last page", "Get me the hell out of this input mode"). And after they'd mandated keys for everything anybody could think of, they had a stroke of genius. They mandated a key that did nothing anybody wanted to do.

    Why is that a stroke of genius?

    It is something rare in engineering, which thrives on bravado and feverishly inflated self-confidence. It is an admission of the limitation of human foresight, an acknowledgement that there are more things under Heaven and Earth than are dreamt of in our philosophies; a semiotic *memento mori*.

    This key is mandated to mean nothing, therefore it can mean anything, or indeed, everything.

    • Re: (Score:3, Funny)

      by itsdapead ( 734413 )

      In fact, to *urgently* tell the OS that the SysRq.

      My first computer, an OSI Superboard 2 had a key for that: "Break". I think it was wired to the reset pin of the 6502.

      That got its attention :-)

  • PrintScreen (Score:3, Insightful)

    by SharpFang ( 651121 ) on Thursday January 14, 2010 @11:21AM (#30764504) Homepage Journal

    I don't care about SysRq but I don't mind it sharing space with PrintScreen. And don't you dare taking my PrintScreen.

  • by Zero__Kelvin ( 151819 ) on Thursday January 14, 2010 @11:23AM (#30764546) Homepage
    They would do better to remove the CAPS LOCK key, which is more bulky and - as far as I know - useful only to morons who don't know how to keep from SHOUTING on the internet. If CAPS LOCK functionality is really needed, they could just allow holding the Shift key for a period longer than t(x). The SysRq key is both the same key as "Print Screen" which is often used and useful, and is a major component of debugging for the most used operating system in the server market (Linux). (Bear in mind that the kernel that runs on those servers gets developed on laptops and desktop workstations, not servers.)


    This is NOT
    their father's Thinkpad.
  • What key again? (Score:3, Insightful)

    by PopeRatzo ( 965947 ) * on Thursday January 14, 2010 @11:29AM (#30764676) Journal

    I'm looking down at my vanilla Logitech keyboard and I don't see any key with "SysRq" on it.

    So I guess I don't need one.

  • by Primitive Pete ( 1703346 ) on Thursday January 14, 2010 @11:32AM (#30764726)
    Frankly, there are a lot of keys we could get rid of, because they just take up real estate and don't help with the way I use the keyboard. I rarely have rekwirements to use the Q key, and I'm kwite sure that others could get by without it, too. These key-friendly users just need to akwire new work habits. What's hard about that?
  • by Tomahawk ( 1343 ) on Thursday January 14, 2010 @11:38AM (#30764826) Homepage

    One major ilk I have about laptop keyboard is the positioning of the CTRL and Fn keys.

    I was in a shop recently that sold laptops of many different brands. All of them, except Lenovo, had the CTRL key as the first key in the row, with the Fn key to the right of it. This, IMHO, is the correct position for it - it's where my little finger automatically goes for CTRL, and where it is located on a 'normal' keyboard.

    Lenovo had the Fn key first, with the CTRL key to the right, meaning that when you go to hit CTRL-, I hit Fn instead. This, for me, is a major factor is choosing what laptop to buy - if the CTRL key is in the wrong place, it's marked off the list immediately.

    funny story:
    Several years ago, for work, I got a Compaq Evo N620c (which I still use for work). While the Fn and CTRL keys are in the wrong place, at least they have the forethought to allow you to swap them in the BIOS, which I naturally did.
    Now, the laptop was to be reburned, so the Service Desk took it in. When I went to pick it up the next day, they had a normal keyboard plugged into the PS/2 socket. I asked them why, and they told me that the CTRL key was broken and they couldn't use CTRL-ALT-DEL (yes, it's Windows. *sigh*)
    So firstly I explained to them that the CTRL and Fn keys were swapped in the BIOS, and then asked the question "Why didn't you just use the CTRL key on the other side of the keyboard?" (which, when tried, worked perfectly).


  • Chiclets (Score:3, Informative)

    by Dr_Barnowl ( 709838 ) on Thursday January 14, 2010 @11:43AM (#30764938)

    The real problem? This laptop has one of those horrible chiclet keyboards.

    Lenovo argues the new design gives the laptop a more "clean and inviting look"

    I don't want to use any keyboard where the look of the thing was given anything more than secondary consideration. I've used chiclet-keys on Powerbooks, and I hate them. And the stupid key layout. I understand that compromises have to be made on a laptop keyboard because of space, but the Powerbook keyboard seems to have been solely designed to "think different" from the standard layout. Thou Shalt Not Move The Slash Keys. Whenever I know I have to support one now, I take my USB keyboard with me, a nice Cherry G80-3000 with a boring, normal, sensible layout, and clicky key switches.

  • by Omeganon ( 104525 ) on Thursday January 14, 2010 @11:52AM (#30765116)

    SysRQ can be extremely useful in figuring out why a machine has locked up or become unresponsive... []

  • by Ralphus Maximus ( 594419 ) on Thursday January 14, 2010 @12:10PM (#30765458)
    For the love of $deity, but the CTRL key back where it frakkin' belongs, next to the frakkin' A key!

    Seriously. CTRL-key combo's are much easier to press, while touch typing, when the CTRL key is just to the left of the A key.

  • Lenovo keyboards (Score:3, Interesting)

    by piojo ( 995934 ) on Thursday January 14, 2010 @12:24PM (#30765700)

    I love the keyboard on my 2.5 year old thinkpad. Especially the dedicated "back" and "forward" buttons, which I've remapped to more useful functions. In fact, I think the keyboard is almost a "killer feature" that none of their competitors can match. If they start removing buttons I use, I may be able to make my next laptop a system76 or clevo.

  • by kalirion ( 728907 ) on Thursday January 14, 2010 @01:03PM (#30766428)

    And why stop there? Lenovo has also asked itself how often users press the F Function keys. On the new laptops, the F Function buttons are reduced to secondary controls, in place of laptop controls like screen brightness. Now, you'll need to hold the Fn button to use keys like F11 (while screen brightness can be pressed without holding Fn).

    Now that is a dumb decision. I use function keys all the time, and having to hold some other key for them to work would definitely be a dealbreaker. My Microsoft keyboard has an "F Lock" key which is like the Fn key but toggleable (think Caps Lock instead of Shift). That's a much better design.

"The Avis WIZARD decides if you get to drive a car. Your head won't touch the pillow of a Sheraton unless their computer says it's okay." -- Arthur Miller