_IO_CONNECT_COMBINE_CLOSE

For a stat() client call, we essentially perform the sequence open()/fstat()/close(). Note that if we actually did that, three messages would be required. For performance reasons, we implement the stat() function as one single combine message:

Client call:

stat()

Message(s):

_IO_CONNECT_COMBINE_CLOSE , _IO_STAT

Callouts:

io_open, io_lock_ocb, io_stat, io_unlock_ocb, io_close

The _IO_CONNECT_COMBINE_CLOSE message causes the io_open handler to be called. It then implicitly (at the end of processing for the combine message) causes the io_close_ocb handler to be called.