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

one use

	golang.org/x/sys/unix (current package)
		ztypes_linux_amd64.go#L128: 	FADV_DONTNEED = 0x4

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