module Select_fds: sig .. end
Wait until some input/output operations become possible on
some channels. The three list arguments are, respectively, a set
of descriptors to check for reading (first argument), for writing
(second argument), or for exceptional conditions (third argument).
The fourth argument is the maximal timeout, in seconds; a
negative fourth argument means no timeout (unbounded wait).
The result is composed of three sets of descriptors: those ready
for reading (first component), ready for writing (second component),
and over which an exceptional condition is pending (third
component).
type
}
val empty : t
val sexp_of_t : t -> Sexplib.Sexp.t