From mint-bounce@lists.fishpool.fi Wed Jan 27 14:51:17 2010 X-ME-UUID: 20100127194821117.02D601C004E3@mwinf2701.orange.fr Date: Wed, 27 Jan 2010 20:48:20 +0100 From: Patrice Mandin To: mint@lists.fishpool.fi Subject: Re: [MiNT] Freeing child's base page Message-Id: <20100127204820.07cbf01c.mandin.patrice@orange.fr> In-Reply-To: <4B60189C.2000806@freesbee.fr> References: <4B5F9E76.7070205@freesbee.fr> <4B6010B7.70306@freesbee.fr> <4B60189C.2000806@freesbee.fr> Organization: Chez moi X-Mailer: Sylpheed 2.5.0 (GTK+ 2.12.12; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-ecartis-version: Ecartis v1.0.0 Sender: mint-bounce@lists.fishpool.fi Errors-to: mint-bounce@lists.fishpool.fi X-original-sender: mandin.patrice@orange.fr Precedence: bulk List-help: List-unsubscribe: List-Id: X-List-ID: List-subscribe: List-owner: List-post: Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.sparemint.org id o0RJpG4q017874 Le Wed, 27 Jan 2010 11:42:36 +0100 Vincent Rivière a écrit: > Miro Kropacek wrote : > > So, if I understand it correctly, when Pexec() returns (using Pterm or > > Pterm0) : > > > > 1. all dynamic memory (using M[x]alloc) is returned back to OS, all > > opened files are closed > > In the normal mode PE_LOADGO (0), I think it is true. But I don't know > hot it behaves in other modes. > > > 2. its text/data/bss segment is still intact, waiting for our Mfree() > > call (and this can be changed by using Pexec (6, ...) but don't want it > > of course) > > Probably true in mode PE_LOAD (3). > > > 3. static variables are in data segment, i.e. point 2 applies here, i.e. > > we can use it as long as basepage isn't free'd > > Yes, sure. > > > However, it seems that MiNT handle special executable flags to share > > the text segment among several process, but I never tried them as > > this is a very specific case. > > > > You mean PE_NOSHARE mode? This is default off, i.e. child's memory is > > shared with parent, so no worries here. > > Yes, this flag. But I didn't understand that flag like you. I understood > it was about sharing the text segment between several process of the > same executable to save the identical RAM. In other words, using the > text segment like a shared library (useful for sh and make). I don't > know if this is still well supported by the kernel and the binutils. > However, as you said, this mode is off by default, it is out of topic here. > > Further information from a kernel guru would be welcome here. Just looking at the compendium, Pexec() on more recent Gemdos versions support PE_GOTHENFREE (6) which automatically frees child memory when the child Pterm() itself. -- Patrice Mandin WWW: http://pmandin.atari.org/ Programmeur Linux, Atari Spécialité: Développement, jeux