From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752584AbbATSQd (ORCPT ); Tue, 20 Jan 2015 13:16:33 -0500 Received: from mail-qc0-f170.google.com ([209.85.216.170]:56166 "EHLO mail-qc0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752458AbbATSQb (ORCPT ); Tue, 20 Jan 2015 13:16:31 -0500 Message-ID: <54BE9B7C.7020709@hurleysoftware.com> Date: Tue, 20 Jan 2015 13:16:28 -0500 From: Peter Hurley User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Howard Chu CC: Greg Kroah-Hartman , One Thousand Gnomes , Jiri Slaby , Linux Kernel Mailing List , linux-serial@vger.kernel.org, "Theodore Ts'o" Subject: Re: [PATCH] n_tty: Remove LINEMODE support References: <1421616632-4077-1-git-send-email-peter@hurleysoftware.com> <54BC3771.7030204@symas.com> <54BC5EC7.1090202@hurleysoftware.com> <54BCFC94.1040605@symas.com> <54BD1B53.9030901@hurleysoftware.com> <54BD328F.9090208@symas.com> <54BD567C.8070200@hurleysoftware.com> <54BD5E54.3050909@symas.com> In-Reply-To: <54BD5E54.3050909@symas.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/19/2015 02:43 PM, Howard Chu wrote: > Peter Hurley wrote: >> On 01/19/2015 11:36 AM, Howard Chu wrote: >>> Peter Hurley wrote: [...] >>>> Which brings up another point: only a pty master should be able to set EXTPROC >>>> mode. Right now, any tty can be set to EXTPROC and the pty slave can even >>>> accidentally unset it. This argues for a new pty ioctl() to set EXTPROC in >>>> termios. pty_set_termios() can silently merge the bit. Another major problem with supporting EXTPROC through termios directly is that Linux does not mask off unsupported termios bits, so the process can't find out directly if the the kernel has this support or doesn't.