Optionally more debug output.

diff --git a/lib/ip/recvfrom.c b/lib/ip/recvfrom.c
index ee09f837f389d4180e0a0a81e1f13930c1fbd84f..7f54de7ed72867f0fcb68285a43903cfa6d69a43 100644 (file)
--- a/lib/ip/recvfrom.c
+++ b/lib/ip/recvfrom.c
@@ -92,6 +92,11 @@ static ssize_t _udp_recvfrom(int socket, void *_RESTRICT buffer, size_t length,
        if (r == -1)
        {
                t_errno= errno;
+#if DEBUG
+               fprintf(stderr, "recvfrom(udp): read failed: %s\n",
+                       strerror(errno));
+               fprintf(stderr, "udp opt flags = 0x%x\n", udpoptp->nwuo_flags);
+#endif
                free(buf);
                errno= t_errno;
                return -1;