Charles-François Natali <neolo...@free.fr> added the comment: > By the way, I've checked mmap(2) manpage -- it looks like the C-version has > nothing > against mmaping 0-sized files, Why does Python's `mmap` still checks file > size?
It doesn't check explicitely that the size is non-0, but rather that the offset is is less than the file size. Passing mmap(2) a 0 length doesn't make much sense anyway - for example, Linux returns EINVAL: http://lxr.free-electrons.com/source/mm/mmap.c?a=avr32#L979 """ unsigned long do_mmap_pgoff(...) [...] if (!len) return -EINVAL; """ >> Do you have an example of a /proc entry with st_size == 0 that can be >> mmapped >> (mapping /proc/sys/debug/exception-trace fails with EACCESS)? > Yes, I've ran into the issue, while trying to mmap /proc/xen/xsd_kva, which > is an > interface to XenBus [1]. Unfortunately, I'm not aware of any other cases. That's what I thought, it's really uncommon: in that case, I'm reluctant to making such a change, for the reason explained above. Ross, Victor? ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue12556> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
