kvm_getloadavg —
get system load averages, from live or dead kernels
Kernel Data Access Library (libkvm, -lkvm)
#include <sys/resource.h>
#include <kvm.h>
int
  
  kvm_getloadavg(kvm_t
    *kd, double
    loadavg[], int
    nelem);
The kvm_getloadavg() function returns the number of
  processes in the system run queue of the kernel or core file, indicated by
  kd. Up to nelem samples are
  retrieved and assigned to successive elements of
  loadavg[]. The system imposes a maximum of 3 samples,
  representing averages over the last 1, 5, and 15 minutes, respectively. On a
  live system, the load average is obtained by calling
  getloadavg(3). If performing
  post mortem on a kernel core file, kvm_getloadavg is
  able to extract the system load averages at the time of death from the core
  file directly.
If the load average was unobtainable, -1 is returned; otherwise, the number of
  samples actually retrieved is returned.