/3rd_party/llvm/autoconf/m4/func_mmap_file.m4
https://code.google.com/p/softart/ · m4 · 26 lines · 20 code · 0 blank · 6 comment · 0 complexity · 96d4ac0e6d3eb82864dd84f334412c3a MD5 · raw file
- #
- # Check for the ability to mmap a file.
- #
- AC_DEFUN([AC_FUNC_MMAP_FILE],
- [AC_CACHE_CHECK(for mmap of files,
- ac_cv_func_mmap_file,
- [ AC_LANG_PUSH([C])
- AC_RUN_IFELSE([
- AC_LANG_PROGRAM([[
- #include <sys/types.h>
- #include <sys/mman.h>
- #include <fcntl.h>
- ]],[[
- int fd;
- fd = creat ("foo",0777);
- fd = (int) mmap (0, 1, PROT_READ, MAP_SHARED, fd, 0);
- unlink ("foo");
- return (fd != (int) MAP_FAILED);]])],
- [ac_cv_func_mmap_file=yes],[ac_cv_func_mmap_file=no],[ac_cv_func_mmap_file=no])
- AC_LANG_POP([C])
- ])
- if test "$ac_cv_func_mmap_file" = yes; then
- AC_DEFINE([HAVE_MMAP_FILE],[],[Define if mmap() can map files into memory])
- AC_SUBST(MMAP_FILE,[yes])
- fi
- ])