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What's A 'Scroll Lock' And Why Is It On My Keyboard?
Jeff Bauer writes "Today's article in The Straight Dope explains all
the weird keys that come with standard PC keyboards. Now if someone could just explain what the 'Alt Graph' key does on my Sun keyboard, enlightement would be at hand ..."
Many people think that scroll lock is now useless, except in Microsoft Excel, but it does have a much more useful purpose, at least in Linux and perhaps BSD.
The Danish keymap is the same on all PC's (and Sun Boxen as well), and we need Alt Graph to access the following characters:
\@${[]}|~?
Not sure about the US keymap, but I sure as hell wouldn't want to go without Alt Graph.
We do not live in the 21st century. We live in the 20 second century.
For example, una says the Macintosh extended keyboards have a scroll lock key. It does not.
Yes it does. It shares the same keycap as F14.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
'clip' is not a program which comes default installed with WinXP. Try it and see.
You must have it installed from somewhere else, or as part of the admin pack or whatever. Its obvioulsy just a program which puts the stdin input into the clipboard, pretty useful, but not included by default.
I.O.U One Sig.
In OSX it is ls | pbcopy
get xclip http://people.debian.org/~kims/xclip/, install, then
$ ls | xclip -i
does what you'd expect.
this dates back to the teletype and is enshrined in the ascii alphabet as Xon and Xoff. Originally it was intended not as a scroll lock but as a way for a teletype or printer to not overflow its fixed hardware buffer. The communication baud rate could easily out pace the tele type printers print speed. when the hardware buffer was nearly full it would send an X-off (contol-s) to the sender to pause its communications. When the buffer was printed the teletype would send a X-on back to the sender to resume spewing.
There was no need for scoll locking functionality on a teletype printer since you could just hold up the paper and look at it back as many lines as you wanted.
but when dumb video terminals came along the terminals could print as fast as the data came in the X-on and X-off functions had little use as a communications protocol, but Now they were useful to humans as a scroll lock. they had at most 40 lines of text and once you scrolled off the top of the screen, you lost that line forever. There were no "windows" or "scroll bars". So you had your fingers poised over the contrl-s key to halt the text from flowing off the screen.
finally along came the PC and Microsoft messed with all the unix converions in their VMS/CPM ripoff called dos: so you could not be sure that control-S would actually work. In part this was because DOS was not really multitasking. programs could take over the OS and capture all the interupts and put hooks directly into the keyboard handler. Since there were no Menus and the "alt" key had not come into its standard defintion yet, the control keys were premium realestate for programs to hook functions into.
thus there was a need for another semaphore. So things like scroll lock and sysRequest, and print screen got added. So yes virgina you can blame MS for these keys as valuable male breasts or an appendix.
Some drink at the fountain of knowledge. Others just gargle.
Correct. clip isn't built in.
.
Clip is one of the utilities from http://www.cmdtools.com/
Well, the clipboard is a property of the environment, rather than the OS. But there's certainly at least one environment that allows this: GNU screen.
Screen has a concept of a buffer file that can be used to store or load the clipboard. The name of this file is defined in your screenrc, so it can vary from system to system, but it's often called /tmp/screen-xchg or (better for multi-user systems) ~/.screen_exchange. The keystroke ^A< reads this file and ^A> writes it; ^A> will also flash up a message telling you what the name of the file is (for example, Copybuffer written to "/tmp/screen-xchg" ).
So what you do is:
And there you have it.
GROGGS: alive and well and living in
If I recall correctly, back in the days of openlook, the props key was used to bring up the properties menu for a window. That's as much as I can remember.
It was used to lock the cursor in place, and the up and down arrow keys scrolled the entire screen, leaving the cursor locked.
I'm not entirely certain what article you thought you read, but according to Una:
The main intent of the Scroll Lock key was to allow scrolling of screen text up, down and presumably sideways using the arrow keys in the days before large displays and graphical scroll bars.
According to you, it sounds like Una got it right at the start.
RTFA
All the mysterious keys are there for you to remap using xmodmap! And having a spare one left over is allways good if a key fails (as a result of piping tea through yourr keyboard). And of course, the windows-key is in the correct place of a meta key, so you could be a better emacs-user in just minutes! And when talking about SysReq, it really is a request to the system, if you gave Magique SysReq compiled in in your Linux-kernel - then press Alt-SysReq-key where key is b to reboot, s to sync disks and r to remount all disks read-only. And this works even if some user-space program fucks up your screen and keyboard...
--The knowledge that you are an idiot, is what distinguishes you from one.
The Scroll Lock was also used by a DOS TSR known as ANSI. When loaded, it allowed scrolling of the entire screen history when the Scroll Lock was on. When you dir a huge folder, you could hit scroll lock and use the arrow keys to navigate the entire list of files. More useful than dir /p...
The Print Screen/SysRq key was used in Dos to send the current screen of text directly to lpt1: (your printer), hence the name "Print Screen". In Windows (all the way back to Windows 3.x), Print Screen executes a screen capture (without the mouse cursor) and puts it on the clipboard. Alt+PrintScreen copies just the current window.
In addition to what was said in the article about Pause/Break, pressing it _during_ a dir or other scrolling text operation will halt the screen. (This includes during booting before the OS loads.) Press any key to continue.
As for the `/~ key? Still haven't found a useful function for it other than typing a ` or a ~.
And the |? That one serves just about the same purpose to me as the "Context Menu" button on many newer keyboards, which is to say, none.
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For people who don't speak english, Alt Gr is pretty useful, as it lets you type accented characters. In EU countries, it is also used to let you type the Euro symbol - Alt-Gr+4 on UK and Irish Keyboards, Alt-Gr+E on most others.