Dogcows Code - chaz/tar/blob - m4/c-bs-a.m4

   1 #serial 2
   2
   3 dnl From Paul Eggert.
   4
   5 AC_DEFUN(AC_C_BACKSLASH_A,
   6 [
   7   AC_CACHE_CHECK([whether backslash-a works in strings], ac_cv_c_backslash_a,
   8    [AC_TRY_COMPILE([],
   9      changequote(<<, >>)dnl
  10      <<
  11 #if '\a' == 'a'
  12       syntax error;
  13 #endif
  14       char buf['\a' == 'a' ? -1 : 1];
  15       buf[0] = '\a';
  16       return buf[0] != "\a"[0];
  17      >>,
  18      changequote([, ])dnl
  19      ac_cv_c_backslash_a=yes,
  20      ac_cv_c_backslash_a=no)])
  21   if test $ac_cv_c_backslash_a = yes; then
  22     AC_DEFINE(HAVE_C_BACKSLASH_A, 1,
  23       [Define if backslash-a works in C strings.])
  24   fi
  25 ])