+ /*
+ * If we just set ctx->len to 0, that means the read operation
+ * has returned end-of-file. Telling that to the main thread
+ * will cause it to set its 'defunct' flag and dispose of the
+ * handle structure at the next opportunity, in which case we
+ * mustn't touch ctx at all after the SetEvent. (Hence we do
+ * even _this_ check before the SetEvent.)
+ */
+ finished = (ctx->len == 0);
+