//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname sync_runtime_Semacquire sync.runtime_Semacquire
func sync_runtime_Semacquire(addr *uint32) {
	semacquire1(addr, false, semaBlockProfile, 0, waitReasonSemacquire)
}

//go:linkname poll_runtime_Semacquire internal/poll.runtime_Semacquire
func poll_runtime_Semacquire(addr *uint32) {
	semacquire1(addr, false, semaBlockProfile, 0, waitReasonSemacquire)
}

	// may be blocking, and that would block the Close.
	// No need for an atomic read of isBlocking, increfAndClose means
	// we have exclusive access to fd.
	if fd.isBlocking == 0 {
		runtime_Semacquire(&fd.csema)
	}

	return err
}

// SetBlocking puts the file into blocking mode.
func (fd *FD) SetBlocking() error {
	if err := fd.incref(); err != nil {
		return err
	}

	}
	// unblock pending reader and writer
	fd.pd.evict()
	err := fd.decref()
	// Wait until the descriptor is closed. If this was the only
	// reference, it is already closed.
	runtime_Semacquire(&fd.csema)
	return err
}

// Windows ReadFile and WSARecv use DWORD (uint32) parameter to pass buffer length.
// This prevents us reading blocks larger than 4GB.
// See golang.org/issue/26923.