BSD 3 development

[unix-history] / usr / src / cmd / uptime.c

#include <stdio.h>
#include <sys/types.h>
#include <a.out.h>
#include <time.h>

struct  tm *localtime();

#define DIV60(t)        ((t+30)/60)    /* x/60 rounded */ 

struct  nlist   nl[] = {
#define X_BOOTIME       0
       { "_bootime" },
#define X_AVENRUN       1
       { "_avenrun" },
       { 0 }
};

time_t  now, bootime;
double  avenrun[3];

int     kmem;

main(argc, argv)
       char **argv;
{
       char obuf[BUFSIZ];
       register int i, days;
       register time_t uptime;
       register struct tm *nowt;

       setbuf(stdout, obuf);
       nlist("/vmunix" , nl);
       if (nl[0].n_value == 0) {
               fprintf(stderr, "No namelist\n");
               exit(1);
       }
       kmem = open("/dev/kmem", 0);
       if (kmem < 0) {
               fprintf(stderr ,"No kmem\n");
               exit(1);
       }
       time(&now);
       nowt = localtime(&now);
       prtat(nowt);
       lseek(kmem, (long)nl[X_BOOTIME].n_value, 0);
       read(kmem, &bootime, sizeof (bootime));
       uptime = now - bootime;
       printf("  up");
       days = uptime / (60*60*24);
       if (days > 0) {
               printf(" %d day%s, ", days, days>1?"s":"");
               uptime %= (60*60*24);
       }
       prttime(DIV60(uptime), "");
       printf("\t\t");
       printf("load average:");
       lseek(kmem, (long)nl[X_AVENRUN].n_value, 0);
       read(kmem, avenrun, sizeof(avenrun));
       for (i = 0; i < 3; i++) {
               printf(" %.2f", avenrun[i]);
               if (i < 2)
                       printf(",");
       }
       printf("\n");
}

prttime(tim, tail)
       time_t tim;
       char *tail;
{
       register int didhrs = 0;

       if (tim >= 60) {
               printf("%3d:", tim/60);
               didhrs++;
       } else {
               printf("    ");
       }
       tim %= 60;
       if (tim > 0 || didhrs) {
               printf(didhrs&&tim<10 ? "%02d" : "%2d", tim);
       } else {
               printf("  ");
       }
       printf("%s", tail);
}

/* prtat prints a 12 hour time given a pointer to a time of day */
prtat(p)
       struct tm *p;
{
       register int t, pm;

       t = p -> tm_hour;
       pm = (t > 11);
       if (t > 11)
               t -= 12;
       if (t == 0)
               t = 12;
       prttime(t*60 + p->tm_min, pm ? "pm" : "am");
}