From owner-freebsd-hackers Thu Feb 18 0:13: 1 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from rover.village.org (rover.village.org [204.144.255.49]) by hub.freebsd.org (Postfix) with SMTP id D3D7E1129A for ; Thu, 18 Feb 1999 00:12:52 -0800 (PST) (envelope-from imp@village.org) Received: from harmony [10.0.0.6] by rover.village.org with esmtp (Exim 1.71 #1) id 10DOZn-0007dh-00; Thu, 18 Feb 1999 01:12:51 -0700 Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.9.2/8.8.3) with ESMTP id BAA66534; Thu, 18 Feb 1999 01:15:44 -0700 (MST) Message-Id: <199902180815.BAA66534@harmony.village.org> To: Stephen McKay Subject: Re: select(2) proposed change Cc: freebsd-hackers@freebsd.org In-reply-to: Your message of "Thu, 18 Feb 1999 17:42:10 +1000." <199902180742.RAA27123@nymph.detir.qld.gov.au> References: <199902180742.RAA27123@nymph.detir.qld.gov.au> <199902180511.WAA65110@harmony.village.org> Date: Thu, 18 Feb 1999 01:15:43 -0700 From: Warner Losh Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <199902180742.RAA27123@nymph.detir.qld.gov.au> Stephen McKay writes: : On Wednesday, 17th February 1999, Warner Losh wrote: : : >Actually, please review these changes. They are closer to english : >than the last one. : : >+Other systems may modify timeout, but no current ones do it by default. : : I am possibly displaying my ignorance, but I thought linux did this : by default. No. Linux used to do this by default, but no longer does it by default. There is a separate system call to do that. I must confess that I do not have a Linux system to absolutely verify this on, however. : >+A future, different system call might modify timeval, but too much legacy : >+code exists which depends on this behavior. : >+Therefore, : >+.Fn select : >+will likely never change to modify timeout. : : I would prefer to keep the fire and brimstone warning. Nothing has been remvoed, the warning is still there. : select() should : be changed to do the subtraction. Select should *NEVER* be changed to do the subtraction. There are *NO* current systems that do this by default. FreeBSD shouldn't change. It is a *********S***T***U***P***I***D********** idea to change the semantics of select(2) at this late stage of the game. I've been there with the Linux experiment back in the 0.99p14 timeframe of Linux. I cannot tell you the number of bogus programs out there that caused 100% cpu usage. If I recall my history correctly, a new system call was added, __bsd_select, which didn't change the timeout parameter. select was #defined to this, unless you did something to prevent it. I think at first this was in the -lbsd library that merged into libc over time and is now the default. I'll check with my Linux running friends to verify things. If you want to create a __linux_select or select2 or some *OTHER* system call that does this for you, then I have no objections. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message