From owner-freebsd-hackers Mon Aug 28 13:43:10 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.FreeBSD.org (8.6.11/8.6.6) id NAA24757 for hackers-outgoing; Mon, 28 Aug 1995 13:43:10 -0700 Received: from kaiwan.kaiwan.com (kaiwan.kaiwan.com [198.178.203.2]) by freefall.FreeBSD.org (8.6.11/8.6.6) with ESMTP id NAA24749 for ; Mon, 28 Aug 1995 13:43:07 -0700 Received: from exit.com (uucp@localhost) by kaiwan.kaiwan.com (8.6.12/8.6.12) with UUCP id NAA17492 for hackers@freefall.FreeBSD.org; Mon, 28 Aug 1995 13:43:04 -0700 *** KAIWAN Internet Access *** Received: (from frank@localhost) by exit.com (8.6.11/8.6.6) id NAA04576 for hackers@freefall.FreeBSD.org; Mon, 28 Aug 1995 13:36:26 -0700 From: Frank Mayhar Message-Id: <199508282036.NAA04576@exit.com> Subject: 16-bit pids? (was Re: 16, 32, and 64bit types?) To: hackers@freefall.FreeBSD.org Date: Mon, 28 Aug 1995 13:36:26 -0700 (PDT) In-Reply-To: <199508282001.GAA12132@godzilla.zeta.org.au> from "Bruce Evans" at Aug 29, 95 06:01:16 am X-Mailer: ELM [version 2.4 PL24 ME5a] Content-Type: text Content-Length: 898 Sender: hackers-owner@FreeBSD.org Precedence: bulk Just an aside, not directly related to the original subject. > Type FreeBSD NetBSDr1994/12) Right > ---- ------- --------------- ----- > min_pid_t - - u16_t (for PID_MAX = 30000) > kernel_pid_t - - kernel_promote(min_pid_t) > pid_t long int32_t user_promote(min_pid_t) Sixteen bits for PID_MAX? Yukko! IMHO, this should be at least 32, and preferably a black-box type (handled by allocate_pid(), not by an int increment, as fast that that might be -- it's still one of the least critical bits of fork()). Some distributed systems need at least 32 bits for the pid, since they add node information, and a black-box type would make this much easier. Granted, it's a nontrivial change, but it would be nice to see some system do it right. I don't think there's any inherent reason why pid_t should be limited to an int (of any size) in modern Un*ces. -- Frank Mayhar frank@exit.com