From nobody Sun Apr 28 18:29:03 2024 X-Original-To: dev-commits-src-branches@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4VSFNJ0pNcz5JjhW; Sun, 28 Apr 2024 18:29:04 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (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 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4VSFNJ08JYz55rn; Sun, 28 Apr 2024 18:29:04 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1714328944; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=q5uYXKXXYQGJEUoQHq5i843AdELygRdOX3RAwUBIqpY=; b=ipZERwADwQWnHfdUNHloanGVnfQQjJad5Dupmd1XtPOMLeDvQxKxd6rG4zgY+Fp+3FGCNa aJOFPT9F1UV+lIvUM/jPTek4yq/xXXNk3dHewI4NhQxigNa8MHT+v50cg/LXiBpUGUN9Ii OCaB9rcK161r644hfD0pzdYFegSU3yrYugrXimsJYrqTTjhlWc9NQ+5KyZBHpGoI5celGL yAHMkblkZbqILVlhTtCZruG/CxO1PK99IAcnN3ag0c5ZoFLayEDl/NkyPtud5mxfntm50t LCCwkVKtgBtPcKsSRqJfmKMmH3kB+tapUiolg9/mwmM4wXW/Dq5iyJRfVDcGSQ== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1714328944; a=rsa-sha256; cv=none; b=eC7S9zS1Y5vSgunm6stAlWBL0uJDiyUBtP87GYUmTtA/0XBYYKomM+WViHkJwKI2QB0usc rmaVYk4ncAyRk8DA6bNLxI9jfcFMTjQy1D9r4xiD3XCwQgUO4uUU4kQ+L6TLNKCzAUD6yh TBE6vlshQJgcCreEHh58WrdeuVpRiNNvO0ZePXcRexEFOSX6nsROiLXXY6XuqSSCzj5I3V aBj41KIxBMthX2rBno4lRhOoC/r47iUcfcAONDW2C2OI/wZb3Zfx7NOpKyix783MC9pHpb lwfQJaVUh4kB1PQX5ccdBtnF9WiYSNdv1yZH8b3ptzpSoLGHDHOR8cYMHjw/pw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1714328944; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=q5uYXKXXYQGJEUoQHq5i843AdELygRdOX3RAwUBIqpY=; b=XFbfEOPDWF26kwH1RUXi5mgGLwp0ctuZF/jvYhYvHYrhw9whj3nP8uqMF4/Be1FAzqS+V3 y9f7bGWoO6N1EdV7BR2cDdM/6yYeWpVB0eSFy88WFIj6MDs//r+IXhpi27YpRUTbMc5Sla Pi5CqvE34O3cAAef8R+YlIXtsjuFv2EekVu8r5JZ9Alls8CUXhDiYxc0AsJ2vYAkXFYY+4 EwYSRZN7tilGCgD3QVdtn7UXtVQKAobXE0YL/YEDyXhc+dZgEsR7HOEZmOxvXGKnelbzv6 OaSokGevt9z3Zyacoh+F9QomAZkai/BmWZXJPhK1ByoS8ytopXyPxQybq+UuZw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4VSFNH6rqQzbtt; Sun, 28 Apr 2024 18:29:03 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 43SIT3Zc026589; Sun, 28 Apr 2024 18:29:03 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 43SIT35b026586; Sun, 28 Apr 2024 18:29:03 GMT (envelope-from git) Date: Sun, 28 Apr 2024 18:29:03 GMT Message-Id: <202404281829.43SIT35b026586@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mateusz Piotrowski <0mp@FreeBSD.org> Subject: git: bb27b83033d0 - stable/14 - sync.8: Document that the "sync dance" is not a thing List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-branches@freebsd.org Sender: owner-dev-commits-src-branches@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: 0mp X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: bb27b83033d0a9a6425ceb508ad51cfb0cf266ea Auto-Submitted: auto-generated The branch stable/14 has been updated by 0mp: URL: https://cgit.FreeBSD.org/src/commit/?id=bb27b83033d0a9a6425ceb508ad51cfb0cf266ea commit bb27b83033d0a9a6425ceb508ad51cfb0cf266ea Author: Mateusz Piotrowski <0mp@FreeBSD.org> AuthorDate: 2024-04-23 14:12:45 +0000 Commit: Mateusz Piotrowski <0mp@FreeBSD.org> CommitDate: 2024-04-28 18:28:43 +0000 sync.8: Document that the "sync dance" is not a thing People still believe that it is essential to run sync(8) a couple of times before a reboot/halt. Document that this has not been necessary for a long time now. Reviewed by: imp, bcr, Pau Amma MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D33233 (cherry picked from commit 177ba183076bd6fe6b29b1d657b954cca256506b) --- bin/sync/sync.8 | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/bin/sync/sync.8 b/bin/sync/sync.8 index 732d813880e2..222e9edf59f9 100644 --- a/bin/sync/sync.8 +++ b/bin/sync/sync.8 @@ -28,7 +28,7 @@ .\" .\" @(#)sync.8 8.1 (Berkeley) 5/31/93 .\" -.Dd May 31, 1993 +.Dd April 25, 2024 .Dt SYNC 8 .Os .Sh NAME @@ -71,3 +71,31 @@ A .Nm utility appeared in .At v4 . +.Pp +On systems older than +.Bx 4.0 , +commands like +.Xr reboot 8 +and +.Xr halt 8 +were unavailable. +The shutdown procedure involved running +.Nm , +waiting for the lights to stop, +and turning off the machine. +.Pp +Issuing three separate +.Nm +commands (one line each) was a placebo that would generally suffice in +.At v7 +machines that were otherwise quiesced systems. +It replaced the one-per-line +.Nm +as a substitute for waiting. +.Pp +.Bx 4.0 +introduced +.Xr reboot 2 +and +.Xr sync 2 +which rendered this trick obsolete.