From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-4.2 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 159A01F8C6 for ; Fri, 30 Jul 2021 09:54:26 +0000 (UTC) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id E8051393CC07 for ; Fri, 30 Jul 2021 09:54:24 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E8051393CC07 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1627638864; bh=YjFv+yMtCjCJoWE42xF+LR2m4usDDfYTl1sXqzQvXeU=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=DI2e3spN+9p+UfJ8miYpeh9fk9XJd2BxyyE/USdNXpAkRXOTRa5czZBnj7DSLTC2l CNnxD99df3PsSrYYPoJMmK7m6L85htZ1IDGLcVnpl9i77vtEevSEZobG3EIR2AQtJF Kf6QyjCs5zas7zmHZ1kQSkBY6rDdWRzVxybFWv1g= Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by sourceware.org (Postfix) with ESMTPS id 6C4B938515DD for ; Fri, 30 Jul 2021 09:54:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 6C4B938515DD Received: by mail.kernel.org (Postfix) with ESMTPSA id 5747860230; Fri, 30 Jul 2021 09:54:04 +0000 (UTC) Received: by pali.im (Postfix) id 24AC6772; Fri, 30 Jul 2021 11:54:02 +0200 (CEST) To: linux-man@vger.kernel.org, Alejandro Colomar , Michael Kerrisk Subject: [PATCH] ioctl_tty.2: Add example how to get or set baudrate on the serial port Date: Fri, 30 Jul 2021 11:53:33 +0200 Message-Id: <20210730095333.6118-1-pali@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: =?utf-8?q?Pali_Roh=C3=A1r_via_Libc-alpha?= Reply-To: =?UTF-8?q?Pali=20Roh=C3=A1r?= Cc: =?UTF-8?q?Marek=20Beh=C3=BAn?= , libc-alpha@sourceware.org Errors-To: libc-alpha-bounces+e=80x24.org@sourceware.org Sender: "Libc-alpha" Signed-off-by: Pali Rohár --- man2/ioctl_tty.2 | 60 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/man2/ioctl_tty.2 b/man2/ioctl_tty.2 index 0b0083c671a7..9d394572ae93 100644 --- a/man2/ioctl_tty.2 +++ b/man2/ioctl_tty.2 @@ -750,6 +750,66 @@ main(void) close(fd); } .EE +.PP +Get or set arbitrary baudrate on the serial port. +.PP +.EX +#include +#include +#include +#include +#include +#include +#include + +int +main(int argc, char *argv[]) +{ +#if !defined(TCGETS2) || !defined(TCSETS2) || !defined(BOTHER) + fprintf(stderr, "TCGETS2, TCSETS2 or BOTHER is unsupported\\n"); + return 1; +#else + struct termios2 tio2; + int fd, rc; + + if (argc != 2 && argc != 3) { + fprintf(stderr, "Usage: %s device [new_baudrate]\\n", argv[0]); + return 1; + } + + fd = open(argv[1], O_RDWR | O_NONBLOCK | O_NOCTTY); + if (fd < 0) { + perror("open"); + return 1; + } + + rc = ioctl(fd, TCGETS2, &tio2); + if (rc) { + perror("TCGETS2"); + close(fd); + return 1; + } + + printf("%u\\n", tio2.c_ospeed); + + if (argc == 3) { + tio2.c_cflag &= ~CBAUD; + tio2.c_cflag |= BOTHER; + tio2.c_ospeed = tio2.c_ispeed = atoi(argv[2]); + + rc = ioctl(fd, TCSETS2, &tio2); + if (rc) { + perror("TCSETS2"); + close(fd); + return 1; + } + } + + close(fd); + return 0; +#endif +} +.EE .SH SEE ALSO .BR ldattach (1), .BR ioctl (2), -- 2.20.1