diff --git a/owlps-listener/owlps-listener.h b/owlps-listener/owlps-listener.h
index ebc245e..96c2c72 100644
--- a/owlps-listener/owlps-listener.h
+++ b/owlps-listener/owlps-listener.h
@@ -480,7 +480,7 @@ void print_version(void) ;
  * false if we are reading from a pcap file.
  */
 #define LIVE_CAPTURING \
-  (! GET_PCAP_FILE())
+  (GET_RTAP_IFACE()[0] != '\0')
 
 
 #endif // _OWLPS_LISTENER_H_
diff --git a/owlps-listener/owlps-listenerd.c b/owlps-listener/owlps-listenerd.c
index 35148f8..ee69e92 100644
--- a/owlps-listener/owlps-listenerd.c
+++ b/owlps-listener/owlps-listenerd.c
@@ -660,7 +660,7 @@ int check_configuration()
     }
 
   // Packet source //
-  if (GET_PCAP_FILE())
+  if (GET_PCAP_FILE() && GET_PCAP_FILE()[0] != '\0')
     {
       if (GET_RTAP_IFACE()[0] != '\0')
         {
@@ -931,7 +931,7 @@ int capture()
 
   if (capture_handler == NULL) // Capture starting failed
     {
-      fprintf(stderr, "Cannot create capture handler on '%s'%s\n",
+      fprintf(stderr, "Cannot create capture handler on '%s': %s\n",
               source, errbuf) ; // Note: errbuf starts with ": "
       return OWL_ERR_IFACE_PCAP_OPEN ;
     }