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The Guy Responsible For Ctrl-Alt-Del
Gannett News is running a story about David Bradley, the IBM engineer who, in 1980, coined Ctrl-Alt-Del. Interestingly, he meant for it to remain a developer-only tool, not something for end users, and certainly not to have Windows users change their passwords or logoff. He also says he chose those keys specifically as it's not a key sequence that can be struck by accident.
Just imagine how much in royalties this guy could have made if he had developed that nowadays with our patent frenzy attitude!
Rich, he would have been rich I tell you!
Mod me down with all of your hatred and your journey towards the dark side will be complete!
As a tech support guy, I just want to give this man a hearty "Thank You"
"I don't have a control key. I have an alt key and this little wavy square, and next to that is a curtl key. And I hit that and backspace and it doesn't do anything."
Thanks, man.
(ps: yes, I know he didn't intend it for the end user. It's a JOKE. Read it, chuckle, give me mod points, and move on)
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Ctrl-Alt-Del is the only key combination on your computer that has its own hardware interrupt (similar to Ctrl-Open Apple/Closed Apple-Reset on Macs). Again, this was to prevent interception in real mode, however protected mode changes all rules.
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
When quake first was released, i didn't want to use the mouse, only the keyboard. However, after doing the shoot-strafe-left-look-down maneuver one time too many, i decided to switch to mouse... (shoot-strafe-left-look-down = ctrl, alt(gr), left arrow, delete)
uh huh...
oh please. He picked a key sequence that's difficult to accidentally set off. So what? It could have been shift-esc-break. If this is what a Ph.D. in electrical engineering is good for, I'm glad I don't have mine.
And the reason MS used it for login in NT 3.1 was for security. It negated the possibility of a impersonation client that displayed an image which looked like the NT 3.1 login, but just stole Passwords instead. If such a client was written to DOS or Windows it would simple reboot. So it was a sanity check, at the time.
-Malakai
A Dragon Lives in my Garage
The author's comparing reseting a dead Windows computer with penicillin. Isn't penicillin used on unwanted infestations of bacteria? Not that far off, if you ask me.
R: That voice. Where have I heard that voice before? B: In about 365 other episodes. But I don't know who it is either.
Many people rag on this, but it actually made some sense at the time. Microsoft has removed it from later versions of Windows for convenience, not security, purposes.
For people who don't know, WIndows NT 4 (and perhaps 3.5 and earlier?) required one to hit CTRL-ALT-DEL to get a login prompt. Many people complained, not seeing the logic in it, but logic there is.
CTRL-ALT-DEL is can never, ever be trapped by an application -- unless Windows has hosed completely, it's guaranteed to get the OS's attention. Having to hit it to get a login box means that no other application can fake a login box. If they tried, CTRL-ALT-DEL would bring up the task manager instead of a login dialog.
So regardless of whether you like it, the minor annoyance served a good purpose and was actually a fairly clever design decision. Much smarter than, oh, allowing macro viruses to execute by default.
This isn't as much "normalization" as it is "don't take so many drugs when you're designing tables."
Bradley says the "strength of the country" is at stake because relatively few students go into science or technology
Why should they when engineers can't find jobs, salesmen are making 6 figures and MBAs are stealing all the money.
Why is it that everyone thinks that Ctrl-Alt-Del has some special hardware interrupt, or something else that makes it magical?
The BIOS traps that combination (through the normal keyboard interrupt) and initiates a system reboot.
Problem is, if your OS isn't using the BIOS for keyboard input (pretty much every modern OS uses it's own keyboard handling code) then the OS determines what this key combination does.
In either case, it is software that determines what that key combination does.
--
"What do you want me to do? Whack a guy? Off a guy? Whack off a guy? Cause I'm married."
The author's comparing reseting a dead Windows computer with penicillin. Isn't penicillin used on unwanted infestations of bacteria? Not that far off, if you ask me.
But CTRL-ALT-DELETE wasn't discovered, as the article states. It was developed. Bradley made it up. Comparing it to the discovery of penicillin is like saying Tolkien discovered the lord of the rings.
i don't like my old sig.
I actually saw a video clip on Tech TV with him and Bill Gates (and someone else but the name eludes me for the moment). They were in some sort of conference and he goes (not a word-for-word quote)"Yes well I'm the one who created CTRL-ALT-DEL, but Bill here is the one who made it famous" ... rousing laughter from the crowd, Bill has the embarassed grin on his face. He allows the laughter to die a little and says "...For Windows NT log-ons!" it was a CLASSIC moment.
On the video, someone made a comment about Ctrl-Alt-Del being a life saver as an easy way to reboot systems after a crash (back when the blue screen stayed up by default). His response was "I just coded the Ctrl-Alt-Del sequence. Bill Gates made it famous." The implication wasn't intentional, but the look on Bill's face was priceless.
Buy the President
Well, aside from your comment indicating you to be a total jackass, there is actually a good reason behind the CTRL-ALT-DEL sequence in NT. It's a security feature.
"The CTRL-ALT-DEL key combination in NT disables user mode programs so a trojan program cannot intercept the user's name and password during the logon process. No user mode programs can be run until a valid logon has occurred. This is called restricted user mode. The CTRL-ALT-DEL key sequence indicates that there is a physically connected keyboard that the keystrokes are coming from. During the logon process, the Winlogon service passes the user's point of authentication, name, and password to the client/server (CSR) subsystem. The CSR passes the information to the security reference monitor which checks the Security Accounts Manager (SAM) database against the received information to see if the user is authentic. If so, a valid access token is generated and returned back down the line to the processes that sent the information."
Read more here.
David Bradley, I give you a three finger salute. Microsoft, I salute you as well, minus two fingers.
I mean, why isn't there a Ctrl-Alt-Gateway or Ctrl-Alt-Compaq? What makes Dell so special?
--Joe
Well, with Pi being proved as infinite and non-repeating, then Lord of the Rings was actually sitting there encoded in Pi forever and would have been sitting there un-discovered had it not been for Tolkien finding it.
That is, that key combo cannot be intercepted by applications thus making it impossible to create infamous fake logins for grabbing user credentials mere looks-like-login-screen
o l\Keyboard Layout registry entry. This changes the key mappings before the system processes ctrl-alt-del.
This is actually untrue. There are several ways to capture ctrl-alt-del in Windows. One is by remapping the keyboard with the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contr
The idea of a secure access key is a good one, but MS has a broken implementation since they allow it to be circumvented.
You can see the video here. My apologies for the crappy news.com link.
Who's the black private dick, who's a sex machine for all the chicks?
This feature is properly known as a SAK - Secure Attention Key. It's an old security feature used to prevent hijacking of trusted consoles, as you said, and is implemented on many systems. The perennial place where it's needed is university computer labs, where logging in and then leaving a fake login prompt running to capture passwords is has always been considered good clean fun. (To implement it properly, one should print a "wrong password!" message, and then exit the user session completely giving the user the real login prompt)
The basic idea is that the OS traps the SAK and does something obvious (like give you a login prompt) to keep a user from running a program pretending to be the OS. Since the OS doesn't let the user handle the SAK, security is maintained.
Linux supports SAK, however it's never really been properly deployed by distributions. Part of the reason is that nobody's ever really standardized on what the SAK key should be. If SysRQ is enabled, than Alt-SysRQ-k will cause a SAK event in the kernel. Otherwise, the keyboard driver can be configured by root to use any key sequence. One key sequence I've seen used is Alt-SysRQ-PageDown, but there's really no particular standard.
When SAK is raised in linux, all programs running on the current terminal are force-killed. It's then expected that init will provide a new login prompt there.
This leads to the second problem with SAK on Linux, namely that most users run X on workstation machines. If you SAK while X is running, the kernel kill -9's X... Which trashes your video card, leaving the system in an unusable state. Which is probably not what you wanted. Some video drivers and cards in X may be stable enough that, if you're running xdm/gdm/kdm etc., it may be able to restart X and give you an X11 login prompt - but the console will still be trashed, so you won't be able to exit out of X afterwards (or eg. with ctrl-alt-f1). It used to be the case that you could store the video settings for your console and run a program (eg. restoretext etc.) to fix them, but that hasn't worked on any modern video card in years. In addition, if you just escape out of X and then fix the console, X will re-trash your console as soon as you return to it, since it only stores the console settings from when X was started, not the current settings. Hence, X and your console program get in a fight and you probably end up crashing the video card and having to pull the power plug out or something if you do this a lot.
Confusing things even more, XFree generally defines its own internal "SAK"-like key sequence, Ctrl-Alt-Backspace. This isn't actually an OS-level SAK though, it just instructs X to quit. And not surprisingly, it often doesn't work due to XFree bugs (and may be trappable by user apps).
Convert LOTR to an integer, then count until you reach it.
Actually, the other day I was generating some really large numbers to look for potential large primes, when I saw a number that struck me as interesting, so I converted the number to binary and dumped it out in a binary file...
Then just yesterday, when trying to do some directory maintenence, I accidentally mistyped a command line and ended up calling perl on the binary file mentioned above. Well, you'd figure that would just give me garbage and die... but to my great surprise, it turns out that that number ended up being identical to a bzip2-compressed stream embedded in a perl script with self-extaction code.
Anyway, to make a long story short, it ended up spitting out the complete LOTR trilogy, nicely formatted in docbook SGML. Sadly, there were some typos, a few dangling reference sto some artwork that I don't have, and oddly enough, it wrote everything into my .gnupg/ directory as files named "bert.smgl", "ernie.sgml", and "bzgbir3.smgl"[sic], so I guess I'll just have to keep looking for interesting numbers and maybe I'll discover a version without these problems.
is written. It's a revelation to some but people like Tolkein, King, etc often don't really know, beyond the inital premise, what's going to happen in their stories. In Stephen King's "On Writing" he claims a creative process that is more discovery than anything else. There isn't an all-encompassing outline drafted ahead of time. He starts out with an idea like "what if there was a cemetary that brought people back to life" and proceeds from there. He likens it to simply catching the story on paper as it falls out of his head. I don't know if this is what Tolkein was talking about but it works for alot of people.