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UNIX for Dummies Questions & Answers
Weird behavior of Vi
Post 302631761 by gary_w on Friday 27th of April 2012 11:25:50 PM
04-28-2012
And now for a trip in the wayback machine.... Regarding the user-friendliness of vi, if you put yourself back in the days when it was written, it was actually very user-friendly, just in different terms then what that means today.
Back in the 70's remote terminals connected to UNIX boxes via phone lines at maybe 300 baud. Can you imagine today writing a program where you type a command, have to wait a sec or 2 to the results, repeat!?
The developers of vi (Bill Joy, etc) made each keystroke count, which meant very short, cryptic commands (that you just plain had to memorize) sure did a lot. You had to minimize that wait time and get the most bang for the keystroke. vi is super-powerful but you just have to learn all those cryptic commands to really be effecient. Why just keep pressing 'l' (that's an ell) to go right when you can press w for word and move faster that direction? Or even better f for find followed by the letter you need to move to? Much quicker once you memorized the movement commands and that is just scratching the surface.
Did you ever wonder why Bill Joy made the left, up, down, right keys h, j, k, l? The first version of vi was developed on the Lear-Siegler ADM-3A, the first terminal with addressable cursor capability which allowed positioning of the cursor at an x,y location on the screen. Before that, text scrolled up just like paper on the teletype machines which preceded the crt tube terminals (still called tty's, short for teletype). Guess which keys had the arrows on them since there were no separate arrow keys yet?
Photo from http://www.tentacle.franken.de/adm3a/
And the Tilda (~) was on the "home" button too, which I assume is where we got the ~ as a shortcut for your home directory.
First the curses library was written in C to support the addressable cursor capability, and right after one of the first real games (and still my favorite), Rogue, was developed to test it they wrote the front end to the ex editor, vi (for visual interface).
Here's a great cheat sheet for vi commands: Vi Cheat Sheet There are others out there too.
Anyway, I hope this historical trip down memory lane makes you appreciate your favorite editor even more when put in the context of the era.
Gary
Back in the 70's remote terminals connected to UNIX boxes via phone lines at maybe 300 baud. Can you imagine today writing a program where you type a command, have to wait a sec or 2 to the results, repeat!?
The developers of vi (Bill Joy, etc) made each keystroke count, which meant very short, cryptic commands (that you just plain had to memorize) sure did a lot. You had to minimize that wait time and get the most bang for the keystroke. vi is super-powerful but you just have to learn all those cryptic commands to really be effecient. Why just keep pressing 'l' (that's an ell) to go right when you can press w for word and move faster that direction? Or even better f for find followed by the letter you need to move to? Much quicker once you memorized the movement commands and that is just scratching the surface.
Did you ever wonder why Bill Joy made the left, up, down, right keys h, j, k, l? The first version of vi was developed on the Lear-Siegler ADM-3A, the first terminal with addressable cursor capability which allowed positioning of the cursor at an x,y location on the screen. Before that, text scrolled up just like paper on the teletype machines which preceded the crt tube terminals (still called tty's, short for teletype). Guess which keys had the arrows on them since there were no separate arrow keys yet?
Photo from http://www.tentacle.franken.de/adm3a/And the Tilda (~) was on the "home" button too, which I assume is where we got the ~ as a shortcut for your home directory.
First the curses library was written in C to support the addressable cursor capability, and right after one of the first real games (and still my favorite), Rogue, was developed to test it they wrote the front end to the ex editor, vi (for visual interface).
Here's a great cheat sheet for vi commands: Vi Cheat Sheet There are others out there too.
Anyway, I hope this historical trip down memory lane makes you appreciate your favorite editor even more when put in the context of the era.
Gary
Last edited by gary_w; 05-02-2012 at 11:54 AM.. Reason: fixed typos
This User Gave Thanks to gary_w For This Post:
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