Change command line processing API to use wchar_t.
Fixes #2128.
diff --git a/Include/pygetopt.h b/Include/pygetopt.h
index 80908be..19e3fd1 100644
--- a/Include/pygetopt.h
+++ b/Include/pygetopt.h
@@ -7,9 +7,9 @@
 
 PyAPI_DATA(int) _PyOS_opterr;
 PyAPI_DATA(int) _PyOS_optind;
-PyAPI_DATA(char *) _PyOS_optarg;
+PyAPI_DATA(wchar_t *) _PyOS_optarg;
 
-PyAPI_FUNC(int) _PyOS_GetOpt(int argc, char **argv, char *optstring);
+PyAPI_FUNC(int) _PyOS_GetOpt(int argc, wchar_t **argv, wchar_t *optstring);
 
 #ifdef __cplusplus
 }