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

one use

	golang.org/x/sys/unix (current package)
		zerrors_linux_amd64.go#L160: 	NS_GET_MNTNS_ID                  = 0x8008b705

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