From 31853ee20c97b03fd9cd74d86f78bca8f507b620 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 13 Jul 2018 10:33:18 +0530
Subject: [PATCH] Handle errno better when polling for events

---
 glfw/backend_utils.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/glfw/backend_utils.c b/glfw/backend_utils.c
index b005ee080..56e075f4d 100644
--- a/glfw/backend_utils.c
+++ b/glfw/backend_utils.c
@@ -222,7 +222,9 @@ pollForEvents(EventLoopData *eld, double timeout) {
 
     while(1) {
         if (timeout >= 0) {
+            errno = 0;
             result = pollWithTimeout(eld->fds, eld->watches_count, timeout);
+            int saved_errno = errno;
             dispatchTimers(eld);
             if (result > 0) {
                 dispatchEvents(eld);
@@ -231,16 +233,18 @@ pollForEvents(EventLoopData *eld, double timeout) {
             }
             timeout = end_time - monotonic();
             if (timeout <= 0) break;
-            if (result < 0 && (errno == EINTR || errno == EAGAIN)) continue;
+            if (result < 0 && (saved_errno == EINTR || saved_errno == EAGAIN)) continue;
             break;
         } else {
+            errno = 0;
             result = poll(eld->fds, eld->watches_count, -1);
+            int saved_errno = errno;
             dispatchTimers(eld);
             if (result > 0) {
                 dispatchEvents(eld);
                 read_ok = eld->watches[0].ready;
             }
-            if (result < 0 && (errno == EINTR || errno == EAGAIN)) continue;
+            if (result < 0 && (saved_errno == EINTR || saved_errno == EAGAIN)) continue;
             break;
         }
     }