First of all thanks for the robust library, which serves just well and allows my project to be cross-platform with very small footprint.

I had been looking for interruptable pollset and created small layer on top of apr_pollset_t in my project based on stable apr-1.2 and apr-1.3 releases.
Meantime I've noticed the following
Changes for APR 1.4.0
  *) Introduce apr_pollset_wakeup() for interrupting the blocking apr_pollset_poll call.
     [Mladen Turk]

Exactly what I need and it just works as intened on Linux, but small note concerning Windows implementation.

Pollset is created with an internal pipe object used to interrupt poll if flags contain APR_POLLSET_WAKEABLE. On Windows, where it's not possible to poll on files, apr_file_socket_pipe_create() function is used to create a dummy pipe and I'm OK with this either. However the descriptor type should be APR_POLL_SOCKET instead of APR_POLL_FILE in this case, otherwise apr_pollset_create() always failes on Windows.

===================================================================
--- apr/poll/unix/select.c    (revision 739958)
+++ apr/poll/unix/select.c    (working copy)
@@ -207,7 +207,7 @@
                                           pollset->pool)) != APR_SUCCESS)
         return rv;
     fd.reqevents = APR_POLLIN;
-    fd.desc_type = APR_POLL_FILE;
+    fd.desc_type = APR_POLL_SOCKET;
     fd.desc.f = pollset->wakeup_pipe[0];

Regards,
Arsen.
www.unimrcp.org