+extern int do_vm_vmtotal(int update_every, usec_t dt);
+extern int do_kern_cp_time(int update_every, usec_t dt);
+extern int do_kern_cp_times(int update_every, usec_t dt);
+extern int do_hw_intcnt(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_intr(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_soft(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_swtch(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_forks(int update_every, usec_t dt);
+extern int do_vm_swap_info(int update_every, usec_t dt);
+extern int do_system_ram(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_swappgs(int update_every, usec_t dt);
+extern int do_vm_stats_sys_v_pgfaults(int update_every, usec_t dt);
+extern int do_kern_ipc_sem(int update_every, usec_t dt);
+extern int do_kern_ipc_shm(int update_every, usec_t dt);
+extern int do_kern_ipc_msq(int update_every, usec_t dt);
+extern int do_uptime(int update_every, usec_t dt);
+extern int do_net_isr(int update_every, usec_t dt);
+extern int do_net_inet_tcp_states(int update_every, usec_t dt);
+extern int do_net_inet_tcp_stats(int update_every, usec_t dt);
+extern int do_net_inet_udp_stats(int update_every, usec_t dt);
+extern int do_net_inet_icmp_stats(int update_every, usec_t dt);
+extern int do_net_inet_ip_stats(int update_every, usec_t dt);
+extern int do_net_inet6_ip6_stats(int update_every, usec_t dt);
+extern int do_net_inet6_icmp6_stats(int update_every, usec_t dt);
+extern int do_getifaddrs(int update_every, usec_t dt);
+extern int do_getmntinfo(int update_every, usec_t dt);
+extern int do_kern_devstat(int update_every, usec_t dt);