From bb7d95ccd129549fc351259fce07ab3b24eb93e4 Mon Sep 17 00:00:00 2001
From: Jeremy Lakeman <jeremy.lakeman@flinders.edu.au>
Date: Mon, 20 Nov 2017 15:05:36 +1030
Subject: [PATCH] Log error reason if we fail to detect interface type from
 reading /sys/net

---
 overlay_interface.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/overlay_interface.c b/overlay_interface.c
index 5d595ae0..5a598416 100644
--- a/overlay_interface.c
+++ b/overlay_interface.c
@@ -1121,6 +1121,7 @@ overlay_interface_register(const char *name,
     // This interface has a symlink to a physical wifi device
     detected_type = OVERLAY_INTERFACE_WIFI;
   }else{
+    WARNF_perror("stat(%s)", path);
     strbuf_reset(sb);
     strbuf_sprintf(sb, "/sys/class/net/%s/speed", name);
     int fd = open(path, O_RDONLY);
@@ -1129,6 +1130,8 @@ overlay_interface_register(const char *name,
       // we *could* read this file to set config based on link speed
       detected_type = OVERLAY_INTERFACE_ETHERNET;
       close(fd);
+    }else{
+      WARNF_perror("open(%s)", path);
     }
   }
 #endif