Added string-from-ptr example.

-- Response to a question asked by Thaddeus L. Olczyk


git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@5489 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/ocaml/string_from_ptr/example_prog.ml

@@ -0,0 +1,23 @@
+(* foo_program.ml -- the program using foolib *)
+
+open Swig    (* Give access to the swig library *)
+open Foolib  (* This is the name of your swig output *)
+
+let results = _foo '()  (* Function names are prefixed with _ in order to make
+			   them lex as identifiers in ocaml.  Consider that
+			   uppercase identifiers are module names in ocaml.
+			   NOTE: the '() syntax is part of swigp4.  You can do:
+		           let results = _foo C_void *)
+
+(* Since your function has a return value in addition to the string output,
+   you'll need to match them as a list *)
+
+let result_string =
+  match results with 
+    C_list [ C_string result_string ; C_int 0 ] -> (* The return value is
+	last when out arguments appear, but this too can be customized.
+	We're also checking that the function succeeded. *)
+      result_string
+  | _ -> raise (Failure "Expected string, int reply from _foo")
+      
+let _ = print_endline result_string