Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!wuarchive!wugate!uunet!yale!cmcl2!phri!roy From: roy@phri.UUCP (Roy Smith) Newsgroups: comp.unix.wizards Subject: Re: TTY, speak now, or forever Message-ID: <4055@phri.UUCP> Date: 25 Oct 89 14:30:01 GMT References: <216100015@s.cs.uiuc.edu> Reply-To: roy@phri.UUCP (Roy Smith) Organization: Public Health Research Institute, NYC, NY Lines: 31 In article <216100015@s.cs.uiuc.edu> voss@s.cs.uiuc.edu writes: > anything NOT in `man 4 tty` that you think I should put in my driver? One of my long-time wants for a tty driver is a 256-long look up table. This is probably a feeping creature, but like all such creatures, it in itself should be trivial to implement (i.e. it's all the *other* creatures which make the kernel so bloated!) Each input character taken off the raw queue is looked up in the table to find out what action should be taken. The two possible actions I have in mind are "echo and buffer in the cooked queue" and "don't echo, put on cooked queue, and cause an input break (i.e. make read(2) return)". You should also be able to cause an input break after a certain number of characters have been typed. The idea is to allow programs like emacs to run in a mode slightly more intelligent than the traditional raw or cbreak modes, but still get at every character it has to when it has to. For most things (i.e. plain printing characters which have not reached the end of the line yet) you can let the kernel do the echoing. Any time an escape character is typed, or the end of a line is reached, you let emacs get control again and decide what needs to be done. Of couse, you need an ioctl to let the user program load its own 256-byte long lookup table. > Is there anything IN `man 4 tty` you think I should NOT put in my driver? Yes, get rid of the proliferation of control structures pretending to have v6 and v7 backwards compatability and start again from scratch. -- Roy Smith, Public Health Research Institute 455 First Avenue, New York, NY 10016 {att,philabs,cmcl2,rutgers,hombre}!phri!roy -or- roy@alanine.phri.nyu.edu "The connector is the network"