func (fd *FD) destroy() error {
	fd.pd.close()
	err := CloseFunc(fd.Sysfd)
	fd.Sysfd = -1
	return err
}
Destroy closes the file descriptor.
package poll
import (
	"io"
	"syscall"
	"github.com/openfresh/gosrt/srtapi"
)
type FD struct {
	fdmu fdMutex
	Sysfd int
	pd pollDesc
}
func (fd *FD) Init(net string, pollable bool) error {
	fd.fdmu.init()
	return fd.pd.init(fd)
}