--- loncom/homework/caparesponse/capa.i	2001/10/29 21:15:44	1.2
+++ loncom/homework/caparesponse/capa.i	2004/03/12 21:06:19	1.3
@@ -2,9 +2,33 @@
 %{
 
 %}
+
+%typemap(perl5,in) char** reterror (char** cvalue) {
+  SV* tempsv;
+  if (!SvROK($source)) {
+    croak("expected a reference\n");
+  }
+  tempsv = SvRV($source);
+  if ((!SvPOK(tempsv))) {
+    croak("expected a double reference\n");
+  }
+  int len;
+  char *temp=SvPV(tempsv,len);
+  cvalue = &temp;
+  $target = cvalue;
+}
+
+%typemap(perl5,argout) char ** reterror {
+  SV *tempsv;
+  tempsv = SvRV($arg);
+  if (($source!=NULL) && (*$source!=NULL)) {
+    sv_setpv(tempsv, *$source);
+    free(*$source);
+  }
+}
 extern int caparesponse_capa_check_answer(char *response,char *correct,
 				   int type,int tol_type,double tolerance,
 				   int sig_lbound,int sig_ubound, 
 				   char *ans_fmt, char *unit_str,
 				   int calc, char *id_list, char *pts_list,
-				   char *rndseed);
+				   char *rndseed, char** reterror);