AC_DEFUN(subdir[_INIT], [
  AC_REQUIRE([COMPAT_FUNC_STRLCPY])
  AC_REQUIRE([COMPAT_FUNC_STRSEP])

  if test -z "$2"; then
    BUFFER_PREFIX="${PACKAGE_NAME}";
  else
    BUFFER_PREFIX="$2";
  fi
  AC_SUBST([BUFFER_PREFIX])

  BUFFER_DIR="$1";
  AC_SUBST([BUFFER_DIR])

  AC_CONFIG_FILES([$1/${BUFFER_PREFIX}_buffer.h:$1/buffer.h.in])
  AC_CONFIG_FILES([$1/${BUFFER_PREFIX}_buffer.c:$1/buffer.c.in])
])