ref: ae1cfc9082b3f56a8502938b892bf0555110a741
dir: /sys/src/libc/9sys/times.c/
#include <u.h> #include <libc.h> static char* skip(char *p) { while(*p == ' ') p++; while(*p != ' ' && *p != 0) p++; return p; } /* * after a fork with fd's copied, both fd's are pointing to * the same Chan structure. Since the offset is kept in the Chan * structure, the seek's and read's in the two processes can be * are competing moving the offset around. Hence the unusual loop * in the middle of this routine. */ long times(long *t) { char b[200], *p; static int f = -1; int i, retries; ulong r; memset(b, 0, sizeof(b)); for(retries = 0; retries < 100; retries++){ if(f < 0) f = open("/dev/cputime", OREAD|OCEXEC); if(f < 0) break; if(seek(f, 0, 0) < 0 || (i = read(f, b, sizeof(b))) < 0){ close(f); f = -1; } else { if(i != 0) break; } } p = b; if(t) t[0] = atol(p); p = skip(p); if(t) t[1] = atol(p); p = skip(p); r = atol(p); if(t){ p = skip(p); t[2] = atol(p); p = skip(p); t[3] = atol(p); } return r; }