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On Fri, Jan 05, 2007 at 08:17:51AM -0800, Christopher Layne wrote: >mmap() is supposed to zero-fill, not refuse to map when len >is less than the system page size. I have never ever seen >mmap() fail to map less than page size on any typical Posix >system. > >" > The system shall always zero-fill any partial page at the end > of an object. Further, the system shall never write out any > modified portions of the last page of an object which are > beyond its end. References within the address range starting > at pa and continuing for len bytes to whole pages following the > end of an object shall result in delivery of a SIGBUS signal. >" > >Back to the original issue, consider this: > >MEM_TOP_DOWN >0x100000 Allocates memory at the highest possible address. > >If there were any kind of simple arithmetic bug behind mmap()'s >scenes (such as computing space to zero-fill, etc. etc.) I would >think ENOMEM would be a very common scenario if we're allocating >near the end of addressible space. % grep "simple arithmetic bug" mmap.cc % Seems fine to me. It's probably a hyperthreaded, dual-core problem. cgf -- 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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