# | |
# 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 | |
]) |