Fixing for foreign-c-requests

README.md

@@ -643,8 +643,8 @@ UTF-8 encoding of the given string.
 
 (**c-utf8->string** _c-bytevector_)
 
-Returns a newly allocated (unless empty) string whose character sequence is
-encoded by the given c-bytevector.
+Returns a newly allocated string whose character sequence is
+encoded by the given c-bytevector. It is an error if _c-bytevector_ is null.
 
 ### Utilities
 

foreign/c/pointer.scm

@@ -76,6 +76,8 @@
 
 (define c-utf8->string
   (lambda (c-bytevector)
+    (when (c-null? c-bytevector)
+      (error "Can not turn null pointer into string"))
     (let ((size (c-strlen c-bytevector)))
       (utf8->string (c-bytevector->bytevector c-bytevector size)))))