diff --git a/pcsc.c b/pcsc.c
index 22bfff9..3b6f788 100644
--- a/pcsc.c
+++ b/pcsc.c
@@ -44,24 +44,49 @@ ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_connect_arginfo, 0, 0, 2)
 	ZEND_ARG_INFO(1, active_protocol)
 ZEND_END_ARG_INFO()
 
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_void, 0, 0, 0)
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_context, 0, 0, 1)
+	ZEND_ARG_INFO(0, context)
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_disconnect, 0, 0, 1)
+	ZEND_ARG_INFO(0, card)
+	ZEND_ARG_INFO(0, disposition)
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_transmit, 0, 0, 2)
+	ZEND_ARG_INFO(0, card)
+	ZEND_ARG_INFO(0, command)
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_card, 0, 0, 1)
+	ZEND_ARG_INFO(0, card)
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_INFO_EX(php_pcsc_scard_errstr, 0, 0, 1)
+	ZEND_ARG_INFO(0, errno)
+ZEND_END_ARG_INFO()
+
 /* {{{ pcsc_functions[]
  *
  * Every user visible function must have an entry in pcsc_functions[].
  */
 zend_function_entry pcsc_functions[] = {
-  PHP_FE(scard_establish_context, NULL)
-  PHP_FE(scard_release_context, NULL)
-  PHP_FE(scard_is_valid_context, NULL)
-  PHP_FE(scard_list_readers, NULL)
+  PHP_FE(scard_establish_context, php_pcsc_scard_void)
+  PHP_FE(scard_release_context, php_pcsc_scard_context)
+  PHP_FE(scard_is_valid_context, php_pcsc_scard_context)
+  PHP_FE(scard_list_readers, php_pcsc_scard_context)
   PHP_FE(scard_connect, php_pcsc_scard_connect_arginfo)
   //PHP_FE(scard_reconnect, NULL)
-  PHP_FE(scard_disconnect, NULL)
-  PHP_FE(scard_transmit, NULL)
-  PHP_FE(scard_status, NULL)
+  PHP_FE(scard_disconnect, php_pcsc_scard_disconnect)
+  PHP_FE(scard_transmit, php_pcsc_scard_transmit)
+  PHP_FE(scard_status, php_pcsc_scard_card)
   //PHP_FE(scard_get_status_change, NULL)
-  PHP_FE(scard_last_errno, NULL)
-  PHP_FE(scard_errstr, NULL)
-  {NULL, NULL, NULL}
+  PHP_FE(scard_last_errno, php_pcsc_scard_void)
+  PHP_FE(scard_errstr, php_pcsc_scard_errstr)
+  PHP_FE_END
 };
 /* }}} */
 
@@ -500,6 +525,10 @@ PHP_FUNCTION(scard_establish_context)
   SCARDCONTEXT scard_context = 0;
   LONG rc = 0;
 
+  if (zend_parse_parameters_none() == FAILURE) {
+    return;
+  }
+
   rc = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, &scard_context);
   if (rc != SCARD_S_SUCCESS)
   {
@@ -796,6 +825,9 @@ PHP_FUNCTION(scard_status)
    Retrieve last error code */
 PHP_FUNCTION(scard_last_errno)
 {
+    if (zend_parse_parameters_none() == FAILURE) {
+      return;
+    }
 	RETURN_LONG(PCSC_G(last_errno));
 }
 /* }}} */