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Xref: sserve comp.unix.programmer:11436 comp.unix.bsd:12517 Newsgroups: comp.unix.programmer,comp.unix.bsd Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!doc.ic.ac.uk!uknet!mcsun!sun4nl!tedux.hobby.nl!mo.hobby.nl!compi.hobby.nl!muts From: muts@compi.hobby.nl (Peter Mutsaers) Subject: mmap for shared memory, how to use efficiently? Sender: muts@compi.hobby.nl (Peter Mutsaers) Organization: My unorganized home Date: Wed, 1 Sep 1993 21:16:24 GMT X-Attribution: PLM Message-ID: <MUTS.93Sep1221625@compi.hobby.nl> Lines: 20 Hello, I want to use mmap to get some memory at a specific memory location (where some global variables exist). It must be shared between 2 processes. I can use a normal file as the shared object, like /tmp/mmap_file. But in that case, the speed is quite low because operations seem to update the real file immediately, therefore the shared memory speed is as low as the disk speed. Can someone help me and tell what the normal/best way is to use mmap; is it possible to open /dev/mem or something like that and then use that as shared object, or is there another device that will not cause disk IO but still be accessible between 2 or more processes? Thanks in advance, -- _______________________________________________________________ Peter Mutsaers, Bunnik (Ut), the Netherlands.