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Aucbvax.4183 fa.editor-p utzoo!decvax!ucbvax!editor.people Fri Oct 2 22:38:57 1981 [CSVAX.MAILER-DAEMON: Unable to deliver mail] >From EAK@MIT-MC Fri Oct 2 17:18:56 1981 Date: 1 Oct 1981 23:09:17-PDT From: CSVAX.MAILER-DAEMON at Berkeley To: EAK Re: Unable to deliver mail

----- Transcript of session follows ----- pots-editor-people... User unknown

----- Unsent message follows ----- >From EAK@MIT-MC Thu Oct 1 23:00:36 1981 Mail-from: ARPANET site MIT-MC rcvd at 1-Oct-81 2237-PDT Date: 2 October 1981 01:33-EDT From: Earl A. Killian <EAK MIT-MC AT> Subject: function keys To: editor-people at SU-SCORE

I thought I'd point out a technique that Robert Wells at BBN used in his editor's command set. He wisely decided that everything should be doable via terminal indepedent control characters, but that function keys should work too when they're available (in a terminal dependent manner).

This would be easy if either 1) all function keys were programmable (in particular the arrow keys), or 2) it was always possible to distinquish a function key from something the user types (e.g. function keys send ^\ X and the ^\ key sends ^\ ^\).

Unfortunately neither of these is true for commercial terminals. However, most (but not all!) terminals prefix their function key sequences with ESC, so he did the next best thing: he did not used the ESC key in the terminal independent command set. Thus ESC A can be made to move up on a VT100, and something else on a C100. The user that wants to edit in a terminal independent manner doesn't care because ESC is not used in any of the commands he uses.

Such are the hacks that are necessary to live in the commercial world.

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