1.0.48.19: another go at fixing the win32 build

[sbcl.git] / doc / manual / ffi.texinfo

diff --git a/doc/manual/ffi.texinfo b/doc/manual/ffi.texinfo
index 12aa045..d6b6d05 100644 (file)
--- a/doc/manual/ffi.texinfo
+++ b/doc/manual/ffi.texinfo
@@ -284,11 +284,13 @@ return zero values.
 
 @item
 @cindex External formats
 
 @item
 @cindex External formats

-The foreign type specifier @code{(sb-alien:c-string &key external-format
-element-type)} is similar to @code{(* char)}, but is interpreted as a
-null-terminated string, and is automatically converted into a Lisp
-string when accessed; or if the pointer is C @code{NULL} or @code{0},
-then accessing it gives Lisp @code{nil}.
+The foreign type specifier @code{(sb-alien:c-string &key
+external-format element-type not-null)} is similar to
+@code{(* char)}, but is interpreted as a null-terminated string, and
+is automatically converted into a Lisp string when accessed; or if the
+pointer is C @code{NULL} or @code{0}, then accessing it gives Lisp
+@code{nil} unless @code{not-null} is true, in which case a type-error
+is signalled.

 
 External format conversion is automatically done when Lisp strings are
 passed to foreign code, or when foreign strings are passed to Lisp code.
 
 External format conversion is automatically done when Lisp strings are
 passed to foreign code, or when foreign strings are passed to Lisp code.