diff --git a/os/access.c b/os/access.c
index b7b19279f..f31626d96 100644
--- a/os/access.c
+++ b/os/access.c
@@ -528,7 +528,7 @@ DefineSelf (int fd)
     ifn.lifn_family = AF_UNSPEC;
     ifn.lifn_flags = 0;
     if (ioctl (fd, SIOCGLIFNUM, (char *) &ifn) < 0)
-        Error ("Getting interface count");    
+        ErrorF ("Getting interface count: %s\n", strerror(errno));
     if (len < (ifn.lifn_count * sizeof(struct lifreq))) {
 	len = ifn.lifn_count * sizeof(struct lifreq);
 	bufptr = malloc(len);
@@ -558,7 +558,7 @@ DefineSelf (int fd)
 #endif
 
     if (ifioctl (fd, IFC_IOCTL_REQ, (pointer) &ifc) < 0)
-        Error ("Getting interface configuration (4)");
+        ErrorF ("Getting interface configuration (4): %s\n", strerror(errno));
 
     cplim = (char *) IFC_IFC_REQ + IFC_IFC_LEN;