1 files changed, 9 insertions, 0 deletions

diff --git a/tests/t_event.c b/tests/t_event.c
index 706a285..1908dc9 100644
--- a/tests/t_event.c
+++ b/tests/t_event.c
@@ -263,9 +263,18 @@ static void case_add_nothing_then_ask(void) {
   pair_close();
 }
 
+/* Whether a worker thread may register a descriptor while this one waits
+   depends on who keeps the set. Tying the answer to the mechanism's name
+   here means a backend added later cannot quietly forget to say. */
+static void case_sharing_matches_the_mechanism(void) {
+  test_case("only a set the kernel keeps may be changed from another thread");
+  CHECK_INT(event_can_share(), strcmp(event_mechanism(), "poll") ? 1 : 0);
+}
+
 void test_event(void) {
   CHECK_INT(event_init(), 0);
   CHECK(event_mechanism() != NULL);
+  case_sharing_matches_the_mechanism();
 
   case_readable();
   case_writable();