Java™ Application Development on Linux - Dator

2.2 Eye to Eye with vi35of their commands . . . and did they make good use of those keys! Virtuallyevery letter is used, both lower and upper case, to mean something unique invi. But don’t be put off by the large number of commands to learn; they fitsome patterns that will make it easy for you to become proficient in a shorttime by learning a few commands and applying the patterns.NOTEIf you really can’t bear to part with your mouse and menus, try gvim. We haven’tused it, but we hear that it has support for mice to help with cut and paste andthe like. After you learn vi and get a little practice, though, you may find thatyou’re never reaching for your mouse any more when you edit.There are three modes to vi: the regular vi mode, some extendedcommands in the ex mode, and the input mode.The simplest mode is the input mode. In input mode, every character youtype becomes part of the text of the file. It’s how you enter the bulk of the textfor your Java programs. But vi doesn’t start up in input mode; you have to “getinto” input mode, and then get back out. Once out, you can use other vicommands to save the text and exit vi. More about those in a bit.NOTEGet out of input mode by pressing the Escape key. You can press it more thanonce, too, just to be sure that you are no longer in input mode. If you are nolonger in input mode and you press escape, it will beep at you—with an audibleor visual notification, depending on how your terminal window is set to respond.In both vim and elvis (two popular vi clones) there is a status line at thebottom of the window that will show if you are in input mode. In vim, lookin the lower left and elvis, the lower right. When in input mode, you will seea status word displayed like insert or replace.In the vi mode, the default mode that you start in, all the keystrokes areinterpreted as commands to the editor. They are not displayed as characters. Sowhen we describe a command, such as dt;, you can type those three charactersbut will not see those characters on your screen. Instead you will see some actiontaken by vi—in this case it will delete text from your cursor up to the firstsemicolon on that line, if any (otherwise it will just beep).