support_format_addrinfo: Include unknown error number in result

2 files changed, 10 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 1f9842518a..fff94307ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2018-04-01  Florian Weimer  <fweimer@redhat.com>
+
+	* support/support_format_addrinfo.c (support_format_addrinfo):
+	Include unknown error number in formatted result.
+
 2018-03-29  Florian Weimer  <fweimer@redhat.com>
 
 	* sysdeps/unix/sysv/linux/i386/tst-bz21269.c (do_test): Also
diff --git a/support/support_format_addrinfo.c b/support/support_format_addrinfo.c
index c5e00e516a..f9dc97c24d 100644
--- a/support/support_format_addrinfo.c
+++ b/support/support_format_addrinfo.c
@@ -220,7 +220,11 @@ support_format_addrinfo (struct addrinfo *ai, int ret)
   xopen_memstream (&mem);
   if (ret != 0)
     {
-      fprintf (mem.out, "error: %s\n", gai_strerror (ret));
+      const char *errmsg = gai_strerror (ret);
+      if (strcmp (errmsg, "Unknown error") == 0)
+        fprintf (mem.out, "error: Unknown error %d\n", ret);
+      else
+        fprintf (mem.out, "error: %s\n", errmsg);
       if (ret == EAI_SYSTEM)
         {
           errno = errno_copy;