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Date: | Fri, 16 Jan 2009 12:24:16 +0000 |
Message-ID: | <ee2e06e90901160424j63c9a2b0u8d6e76bd8bb352c1@mail.gmail.com> |
Subject: | how to get mmap page size? |
From: | Jay Foad <jay DOT foad AT gmail DOT com> |
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I have an application that wants to use mmap() to read a file, but only if it can guarantee that this will leave one or more zero bytes after the end of the contents of the file in memory: if ((filesize & (pagesize - 1) != 0) use_mmap(); else use_read(); How do I get the appropriate page size on cygwin? If I call getpagesize() it returns 64k, the "allocation granularity". Internally cygwin has a getsystempagesize() (introduced here: http://cygwin.com/ml/cygwin-cvs/2005-q4/msg00099.html) that returns the appropriate page size, 4k, but that doesn't seem to be exposed to applications. I know that this has been discussed before, e.g. here: http://www.cygwin.com/ml/cygwin/2002-01/msg00747.html but I haven't found an answer to this particular question. Thanks, Jay. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
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