References: golang.org/x/sys/unix.PTP_PF

const golang.org/x/sys/unix.PTP_PF_EXTTS

one use

	golang.org/x/sys/unix (current package)
		ztypes_linux.go#L4267: 	PTP_PF_EXTTS   = 0x1

The pages are generated with Golds v0.7.6. (GOOS=linux GOARCH=amd64)