Path: utzoo!attcan!uunet!fub!geminix.in-berlin.de!gemini From: gemini@geminix.in-berlin.de (Uwe Doering) Newsgroups: comp.unix.sysv386 Subject: Re: Missing SysV tty device driver feature?? Message-ID: Date: 24 Jan 91 11:58:11 GMT References: <82177@unix.cis.pitt.edu> <1991Jan23.034042.3368@NCoast.ORG> Organization: Private UNIX Site Lines: 24 allbery@NCoast.ORG (Brandon S. Allbery KB8JRR) writes: >The System V tty driver defaults to "non-CLOCAL" mode. This mode is >characterized by two system actions: > >- if all processes in the process group exit, DTR is dropped by the computer. In most SysV tty drivers the assertion of DTR doesn't depend on the CLOCAL flag. It is always raised if at least one process has opened the device, and is dropped if the last process closes the device. This is implementation dependent because the termio(7) man page isn't very clear about what lines belong to the modem control group. Although, the man page clearly states that the HUPCL flag determines whether the DTR line is to be dropped with the last close or not. Therefor, I think controlling the behaviour of DTR with the HUPCL flag instead of CLOCAL is the right thing to do. Uwe -- Uwe Doering | INET : gemini@geminix.in-berlin.de Berlin |---------------------------------------------------------------- Germany | UUCP : ...!unido!fub!geminix.in-berlin.de!gemini