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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.
'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.
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/