1 # 2 # Check for the ability to mmap a file. 3 # 4 AC_DEFUN([AC_FUNC_MMAP_FILE], 5 [AC_CACHE_CHECK(for mmap of files, 6 ac_cv_func_mmap_file, 7 [ AC_LANG_PUSH([C]) 8 AC_RUN_IFELSE([ 9 AC_LANG_PROGRAM([[ 10 #include <sys/types.h> 11 #include <sys/mman.h> 12 #include <fcntl.h> 13 ]],[[ 14 int fd; 15 fd = creat ("foo",0777); 16 fd = (int) mmap (0, 1, PROT_READ, MAP_SHARED, fd, 0); 17 unlink ("foo"); 18 return (fd != (int) MAP_FAILED);]])], 19 [ac_cv_func_mmap_file=yes],[ac_cv_func_mmap_file=no],[ac_cv_func_mmap_file=no]) 20 AC_LANG_POP([C]) 21 ]) 22 if test "$ac_cv_func_mmap_file" = yes; then 23 AC_DEFINE([HAVE_MMAP_FILE],[],[Define if mmap() can map files into memory]) 24 AC_SUBST(MMAP_FILE,[yes]) 25 fi 26 ]) 27
