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Newsgroups: comp.os.386bsd.development Path: sserve!newshost.anu.edu.au!munnari.oz.au!spool.mu.edu!howland.reston.ans.net!gatech!swrinde!news.dell.com!pmafire!mica-nsf.inel.gov!cwis.isu.edu!fcom.cc.utah.edu!cs.weber.edu!terry From: terry@cs.weber.edu (A Wizard of Earth C) Subject: Re: Naming convention for tty-like devices Message-ID: <1993May8.065024.5004@fcom.cc.utah.edu> Sender: news@fcom.cc.utah.edu Organization: Weber State University (Ogden, UT) References: <1993May7.140046.1826@gmd.de> Date: Sat, 8 May 93 06:50:24 GMT Lines: 42 In article <1993May7.140046.1826@gmd.de> veit@mururoa.gmd.de (Holger Veit) writes: >This seems to be a never-ending story: the problem to >find a homogenous naming convention for tty-like >devices. [ ... ] >So we should negotiate a naming scheme for all these >devices. My proposal is the following: > >pseudo ttys: tty[pqrst][0-9a-f] >dialin serial: ttyd[0-9a-f] >dialout serial: cua[0-9a-f] >non-bidirectional serial: com[0-9a-f] or ttyd[0-9a-f] >virtual consoles: tty[0-9][0-9] > >We should discuss this and decide then. Why do we need different "non-bidirectional serial" and "dialin serial" devices? Why aren't they the same? Modem control? If so, the modem control should be allowed to be ignored using the partial open hack, so no distinction needs to be made. The initial distinction was made when people started hooking misconfigured modems to UNIX systems; I don't know if Microport, Sun, or Cubix was the first company that started the "three devices per device" abomination, but there's no reason to perpetuate it. The "partial open hack" forces a modem device open without carrier: 1) open the device with O_NDELAY (ignore carrier) returning tmpfd 2) open the device without O_NDELAY returning fd 3) close tmpfd from the first open. This can only work if CLOCAL is correctly implemented, but once that's done, there's no problem. It's secondary use is as a tag in gettytab to indicate a getty on a direct line. Terry Lambert terry@icarus.weber.edu --- Any opinions in this posting are my own and not those of my present or previous employers.