A file descriptor for signal handling.
This can be used for synchronous signal handling using
(blocking) `readSignalfd` directly, or for asynchronous signal handling
using `epoll`.
Totality: total
Visibility: export
Constructor: TFD : Bits32 -> Timerfd
Projection: .fd : Timerfd -> Bits32
Hints:
Cast Timerfd Fd Cast Bits32 Timerfd Cast CInt Timerfd