조각코드 : 시스템 부팅 후 경과시간 검사

int uptime();

int main()
{
    time_t cutime = uptime();
    time_t starttime = time((time_t *)NULL)  - cutime;
    printf("Uptime is %d sec\n", (unsigned int)cutime);
    printf("Booting time is %s\n",time2str(starttime, "y/m/d/ D h:mi:s"));
    return 0;
}

# ./uptime 
Uptime is 55489 sec
Booting time is 2004/02/01/ 일 01:50:42

#include <stdio.h>
#include <time.h>
#include "time2str.h"

#ifdef _SOLARIS_
#include <kstat.h>
#endif

#include <stdio.h>

int uptime()
{
  double stime;
  double idletime;
#ifdef _LINUX_
  char buf[36];
  FILE *fp;
  if ((fp = fopen("/proc/uptime", "r")) == NULL)
  {
    return -1;
  }

  fgets(buf, 36, fp);
  sscanf(buf, "%lf %lf", &stime, &idletime);
  fclose(fp);

  return (int)stime;
#endif

#ifdef _SOLARIS_
  kstat_ctl_t *kc;
  kstat_t *ks;
  kid_t kid;
  kstat_named_t *named;
  int i;

  kc = kstat_open();
  if(kc == NULL)
  {
    perror("kstat_open");
    exit(0);
  }

  ks = kstat_lookup(kc, "unix", -1, "system_misc");
  kid = kstat_read(kc, ks, NULL);
  named = kstat_data_lookup(ks, "lbolt");
  return (named->value.ul)/100;
#endif
}