Add more context to the error messages

[fio.git] / engines / skeleton_external.c

diff --git a/engines/skeleton_external.c b/engines/skeleton_external.c
index 2c330f0c3f69e05ea4663dcd1157bbd3f233c68c..0937d68562be1b196049a61ae858f4143e9041e5 100644 (file)
--- a/engines/skeleton_external.c
+++ b/engines/skeleton_external.c
@@ -57,10 +57,21 @@ static int fio_skeleton_cancel(struct thread_data *td, struct io_u *io_u)
  * The ->queue() hook is responsible for initiating io on the io_u
  * being passed in. If the io engine is a synchronous one, io may complete
  * before ->queue() returns. Required.
+ *
+ * The io engine must transfer in the direction noted by io_u->ddir
+ * to the buffer pointed to by io_u->xfer_buf for as many bytes as
+ * io_u->xfer_buflen. Residual data count may be set in io_u->residual
+ * for a short read/write.
  */
 static int fio_skeleton_queue(struct thread_data *td, struct io_u *io_u)
 {
-       return 0;
+       /*
+        * Could return FIO_Q_QUEUED for a queued request,
+        * FIO_Q_COMPLETED for a completed request, and FIO_Q_BUSY
+        * if we could queue no more at this point (you'd have to
+        * define ->commit() to handle that.
+        */
+       return FIO_Q_COMPLETED;
 }
 
 /*