source: branches/libc-0.6/src/libctests/glibc/time/tst-posixtz.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

struct
{
  time_t when;
  const char *tz;
  const char *result;
} tests[] =
{
  { 909312849L, "AEST-10AEDST-11,M10.5.0,M3.5.0",
    "1998/10/25 21:54:09 dst=1 zone=AEDST" },
  { 924864849L, "AEST-10AEDST-11,M10.5.0,M3.5.0",
    "1999/04/23 20:54:09 dst=0 zone=AEST" },
  { 919973892L, "AEST-10AEDST-11,M10.5.0,M3.5.0",
    "1999/02/26 07:18:12 dst=1 zone=AEDST" },
  { 909312849L, "EST+5EDT,M4.1.0/2,M10.5.0/2",
    "1998/10/25 05:54:09 dst=0 zone=EST" },
  { 924864849L, "EST+5EDT,M4.1.0/2,M10.5.0/2",
    "1999/04/23 06:54:09 dst=1 zone=EDT" },
  { 919973892L, "EST+5EDT,M4.1.0/2,M10.5.0/2",
    "1999/02/25 15:18:12 dst=0 zone=EST" },
};

int
main (void)
{
  int result = 0;
  size_t cnt;

  for (cnt = 0; cnt < sizeof (tests) / sizeof (tests[0]); ++cnt)
    {
      char buf[100];
      struct tm *tmp;

      printf ("TZ = \"%s\", time = %ld => ", tests[cnt].tz, tests[cnt].when);
      fflush (stdout);

      setenv ("TZ", tests[cnt].tz, 1);

      tmp = localtime (&tests[cnt].when);

      snprintf (buf, sizeof (buf),
                "%04d/%02d/%02d %02d:%02d:%02d dst=%d zone=%s",
                tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday,
                tmp->tm_hour, tmp->tm_min, tmp->tm_sec, tmp->tm_isdst,
                tzname[tmp->tm_isdst ? 1 : 0]);

      fputs (buf, stdout);

      if (strcmp (buf, tests[cnt].result) == 0)
        puts (", OK");
      else
        {
          result = 1;
          puts (", FAIL");
        }
    }

  setenv ("TZ", "Universal", 1);
  localtime (&tests[0].when);
  printf ("TZ = \"Universal\" daylight %d tzname = { \"%s\", \"%s\" }",
          daylight, tzname[0], tzname[1]);
  if (! daylight)
    puts (", OK");
  else
    {
      result = 1;
      puts (", FAIL");
    }

  setenv ("TZ", "AEST-10AEDST-11,M10.5.0,M3.5.0", 1);
  tzset ();
  printf ("TZ = \"AEST-10AEDST-11,M10.5.0,M3.5.0\" daylight %d"
          " tzname = { \"%s\", \"%s\" }", daylight, tzname[0], tzname[1]);
  if (daylight
      && strcmp (tzname[0], "AEST") == 0 && strcmp (tzname[1], "AEDST") == 0)
    puts (", OK");
  else
    {
      result = 1;
      puts (", FAIL");
    }

  return result;
}