From 6b71351138911ad5435744ebdc87fb72f5ab09c0 Mon Sep 17 00:00:00 2001
From: John Hood <cgull@glup.org>
Date: Mon, 28 Dec 2015 06:09:11 -0500
Subject: [PATCH] select.h: workaround and report Cygwin select() bug

Resolves #705.
---
 src/util/select.h | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/util/select.h b/src/util/select.h
index 4b4834b..82ffc7b 100644
--- a/src/util/select.h
+++ b/src/util/select.h
@@ -149,7 +149,15 @@ public:
     }
 #endif
 
-    if ( ( ret == -1 ) && ( errno == EINTR ) ) {
+    if ( ret == 0 || ( ret == -1 && errno == EINTR ) ) {
+      /* Look for and report Cygwin select() bug. */
+      if ( ret == 0 ) {
+	for ( int fd = 0; fd <= max_fd; fd++ ) {
+	  if ( FD_ISSET( fd, &read_fds ) ) {
+	    fprintf( stderr, "select(): nfds = 0 but read fd %d is set\n", fd );
+	  }
+	}
+      }
       /* The user should process events as usual. */
       FD_ZERO( &read_fds );
       ret = 0;