select() errors and AnyEvent::Loop

[Felipe Gasper]

> On Jun 1, 2021, at 2:08 PM, Felipe Gasper <felipe at felipegasper.com> wrote:
> 
> Hi all,
> 
> 	I’ve noticed that AnyEvent::Loop doesn’t check for select() failures. Is this by design?
> 
> 	In my testing it leads to a tight loop if, e.g., a file descriptor gets closed from underneath (possible w/ buggy XS modules or misuse of POSIX::close()) or if ENOMEM happens.

Pursuant to this: what if the following were added?

-----
diff --git a/lib/AnyEvent/Loop.pm b/lib/AnyEvent/Loop.pm
index fb9351a..5015e1e 100644
--- a/lib/AnyEvent/Loop.pm
+++ b/lib/AnyEvent/Loop.pm
@@ -254,6 +254,8 @@ sub one_event {
          CORE::select undef, undef, undef, $wait if $wait;
       } elsif (!@timer || $timer[0][0] > $MNOW && !$fds) {
          $$$_ && $$$_->() for @idle = grep $$$_, @idle;
+      } elsif (-1 == $fds) {
+         die "select(): $!";
       }
    }
 }
-----

-FG