ref: 2985d53b7a06d8a1712493aa899d6ffcfacd9e3b
dir: /sys/src/libc/9sys/cputime.c/
#include <u.h> #include <libc.h> #define HZ 1000 double cputime(void) { long t[4]; long times(long*); int i; times(t); for(i=1; i<4; i++) t[0] += t[i]; return t[0] / (double)HZ; }