class virtualUse[[> 'a file_state_t ]]
file :[< rwx_t ] -> Unix.file_descr ->
object
..end
inherit file rwx fd
to derive an I/O event object that waits for the
file descriptor fd
to be ready for reading, writing, or exception
(according to the value of rwx
).method private virtual service : t -> ([> 'a file_state_t ] as 'b)
fd
is ready for I/O. If the value returned is `Working
(mux, v)
, then subsequent applications of self#canget
will
return true
and self#get
will return v
, but the event will
remain loaded in the polling mux waiting for further events on the
file descriptor fd
.
Note: this type of this method is less general than its declaration
in the event
class type. Its return type is constrained by
also including the `Working of t * 'a
variant.