Error thrown for read only pvar in assignment left side (#98)

kamailio/websockets-role.cfg

@@ -106,7 +106,7 @@ event_route[xhttp:request]
     }
 
     if (ws_handle_handshake()) {
-        $shtinc(websockets=>$si::count);
+        $var(shtinc) = $shtinc(websockets=>$si::count);
         xlog("L_INFO", "websocket|log|opened websocket $var(count) of 50 for $si:$sp\n");
         exit;
     }
@@ -116,7 +116,7 @@ event_route[xhttp:request]
 }
 
 event_route[websocket:closed] {
-    $shtdec(websockets=>$si::count);
+    $var(shtdec) = $shtdec(websockets=>$si::count);
     if ($sht(websockets=>$si::count) < 1) {
         xlog("L_INFO", "websocket|log|$si:$sp closed last websocket to that IP\n");
         sht_rm_name_re(websockets=>$(si{re.subst,/\\./\\\\./g})::.*);