1 files changed, 3 insertions, 0 deletions
diff --git a/thread.c b/thread.c
index 2f768b2cab..01689ffeb8 100644
--- a/thread.c
+++ b/thread.c
@@ -2018,6 +2018,9 @@ rb_thread_wait_fd_rw(int fd, int read)
     int result = 0;
     thread_debug("rb_thread_wait_fd_rw(%d, %s)\n", fd, read ? "read" : "write");
 
+    if (fd < 0) {
+	rb_raise(rb_eIOError, "closed stream");
+    }
     while (result <= 0) {
 	rb_fdset_t set;
 	rb_fd_init(&set);