Hi, Eric Gallager wrote: > Hi, I was just writing because I noticed a few nits with gnulib's > documentation of mmap here: > https://www.gnu.org/software/gnulib/manual/html_node/mmap.html > 1. there's a missing close-parenthesis after "even without MAP_FIXED"
Thanks; fixed: https://git.savannah.gnu.org/gitweb/?p=gnulib.git;a=commitdiff;h=5d2d12d7b5aeb023a2e45f5625a07777564caa27 > 2. there's no discussion of how sometimes MAP_ANONYMOUS is written as > just MAP_ANON instead. This is an issue with the header file <sys/mman.h>, not with the function mmap(). Therefore it would have to be documented in https://www.gnu.org/software/gnulib/manual/html_node/sys_002fmman_002eh.html But in fact, POSIX does not require MAP_ANONYMOUS nor MAP_ANON, see https://pubs.opengroup.org/onlinepubs/9699919799.2018edition/basedefs/sys_mman.h.html, and Gnulib does not correct it (one way or the other). > This GitHub issue for libressl-portable has a > (probably outdated) table covering which platforms support which > spelling: https://github.com/libressl-portable/portable/issues/24 Gnulib also has this info, in m4/mmap-anon.m4 (dating from 2009): # - On Linux, AIX, OSF/1, Solaris, Cygwin, Interix, Haiku, both MAP_ANONYMOUS # and MAP_ANON exist and have the same value. # - On HP-UX, only MAP_ANONYMOUS exists. # - On Mac OS X, FreeBSD, NetBSD, OpenBSD, Minix, only MAP_ANON exists. # - On IRIX, neither exists, and a file descriptor opened to /dev/zero must be # used. Meanwhile, Mac OS X and the BSDs also support both spellings: # - On Linux, Mac OS X, FreeBSD, NetBSD, OpenBSD, AIX, OSF/1, Solaris, Cygwin, # Interix, Haiku, both MAP_ANONYMOUS and MAP_ANON exist and have the same value. # - On HP-UX, only MAP_ANONYMOUS exists. # - On Minix, only MAP_ANON exists. # - On IRIX, neither exists, and a file descriptor opened to /dev/zero must be # used. HP-UX, Minix, IRIX are no longer relevant for most programs. Therefore it's nowadays OK to use either MAP_ANONYMOUS or MAP_ANON, and both will work. Bruno
