From owner-freebsd-hackers Sun Jun 18 23:28: 0 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from rover.village.org (rover.village.org [204.144.255.49]) by hub.freebsd.org (Postfix) with ESMTP id 5BEFB37BC24 for ; Sun, 18 Jun 2000 23:27:56 -0700 (PDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (harmony.village.org [10.0.0.6]) by rover.village.org (8.9.3/8.9.3) with ESMTP id AAA32687; Mon, 19 Jun 2000 00:27:54 -0600 (MDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.9.3/8.8.3) with ESMTP id AAA54456; Mon, 19 Jun 2000 00:26:30 -0600 (MDT) Message-Id: <200006190626.AAA54456@harmony.village.org> To: "Shawn Workman" Subject: Re: Sharing memory between processes. Cc: freebsd-hackers@FreeBSD.ORG In-reply-to: Your message of "Sun, 18 Jun 2000 23:06:24 PDT." <007301bfd9b4$8018c1b0$b2a612d8@hayden> References: <007301bfd9b4$8018c1b0$b2a612d8@hayden> Date: Mon, 19 Jun 2000 00:26:30 -0600 From: Warner Losh Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <007301bfd9b4$8018c1b0$b2a612d8@hayden> "Shawn Workman" writes: : Is there a way to give a client app access to another apps memory? = Yes. It is called system V shared memory. mmap will also be able to do that as well, if you use a backing file (is that still required?) : I have used the shm* functions and from what I see I am limited to = : the number of shared memory pointers I can have. You are limited by the number of shared memory areas you can have, and their size. You can have any number of pointers into this memory that you want. You'll need to come up with some kind of wrapper for this stuff as well. Also, there are no guarantees, iirc, that the shared memory segment will be at the same virtual address in both processes, so pointers in one program won't work in the other w/o a translation, which can be, ahhhh, tricky. : I would really appreciate any help that could be provided here. I = : have been looking at the possibility of an lkm but hear that this can = : cause the system to become unstable.. Just use shm*. You will be much happier. Trust me. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message