ESUCCESS = 0 is not true, but exists.

p4raw-id: //depot/perl@20535

diff --git a/ext/Errno/t/Errno.t b/ext/Errno/t/Errno.t
index 02f5ce2..a879cf2 100755 (executable)
--- a/ext/Errno/t/Errno.t
+++ b/ext/Errno/t/Errno.t
@@ -26,7 +26,8 @@ print "not " unless &{"Errno::$err"} == $num;
 print "ok 2\n";
 
 $! = $num;
-print "not " unless $!{$err};
+# Some systems have ESUCCESS 0, that's why exists instead of boolean.
+print "not " unless exists $!{$err};
 print "ok 3\n";
 
 $! = 0;