const syscall.SO_KEEPALIVE

2 uses

	syscall (current package)
		zerrors_linux_amd64.go#L1012: 	SO_KEEPALIVE                     = 0x9

	net
		sockopt_posix.go#L117: 	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive))