From 097c2011e19181e84501d1e1aa0fdd62e76463b2 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Sun, 10 Jan 2016 21:26:35 +1100
Subject: [PATCH] HAL_SITL: prevent abort on select with -1 fd

---
 libraries/AP_HAL_SITL/UARTDriver.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libraries/AP_HAL_SITL/UARTDriver.cpp b/libraries/AP_HAL_SITL/UARTDriver.cpp
index d954838188..5ca6cb5b96 100644
--- a/libraries/AP_HAL_SITL/UARTDriver.cpp
+++ b/libraries/AP_HAL_SITL/UARTDriver.cpp
@@ -385,6 +385,9 @@ void UARTDriver::_set_nonblocking(int fd)
 
 void UARTDriver::_timer_tick(void)
 {
+    if (!_connected) {
+        return;
+    }
     uint32_t navail;
     ssize_t nwritten;