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#!perl -w

use strict;

use Config;
use POSIX;
use Test::More tests => 19;

# go to UTC to avoid DST issues around the world when testing.  SUS3 says that
# null should get you UTC, but some environments want the explicit names.
# Those with a working tzset() should be able to use the TZ below.
$ENV{TZ} = "UTC0UTC";

SKIP: {
    # It looks like POSIX.xs claims that only VMS and Mac OS traditional
    # don't have tzset().  Win32 works to call the function, but it doesn't
    # actually do anything.  Cygwin works in some places, but not others.  The
    # other Win32's below are guesses.
    skip "No tzset()", 2
       if $^O eq "MacOS" || $^O eq "VMS" || $^O eq "cygwin" || $^O eq "djgpp" ||
          $^O eq "MSWin32" || $^O eq "dos" || $^O eq "interix";
    tzset();
    my @tzname = tzname();
    like($tzname[0], qr/(GMT|UTC)/i, "tzset() to GMT/UTC");
    SKIP: {
        skip "Mac OS X/Darwin doesn't handle this", 1 if $^O =~ /darwin/i;
        like($tzname[1], qr/(GMT|UTC)/i, "The whole year?");
    }
}

if ($^O eq "hpux" && $Config{osvers} >= 11.3) {
    # HP does not support UTC0UTC and/or GMT0GMT, as they state that this is
    # legal syntax but as it has no DST rule, it cannot be used. That is the
    # conclusion of bug
    # QXCR1000896916: Some timezone valuesfailing on 11.31 that work on 11.23
    $ENV{TZ} = "UTC";
}

# asctime and ctime...Let's stay below INT_MAX for 32-bits and
# positive for some picky systems.

is(asctime(CORE::localtime(0)), ctime(0), "asctime() and ctime() at zero");
is(asctime(POSIX::localtime(0)), ctime(0), "asctime() and ctime() at zero");
is(asctime(CORE::localtime(12345678)), ctime(12345678),
   "asctime() and ctime() at 12345678");
is(asctime(POSIX::localtime(12345678)), ctime(12345678),
   "asctime() and ctime() at 12345678");

# Careful!  strftime() is locale sensitive.  Let's take care of that
my $orig_loc = setlocale(LC_TIME, "C") || die "Cannot setlocale() to C:  $!";
my $jan_16 = 15 * 86400;
is(ctime($jan_16), strftime("%a %b %d %H:%M:%S %Y\n", CORE::localtime($jan_16)),
        "get ctime() equal to strftime()");
is(ctime($jan_16), strftime("%a %b %d %H:%M:%S %Y\n", POSIX::localtime($jan_16)),
        "get ctime() equal to strftime()");
is(strftime("%Y\x{5e74}%m\x{6708}%d\x{65e5}", CORE::gmtime($jan_16)),
   "1970\x{5e74}01\x{6708}16\x{65e5}",
   "strftime() can handle unicode chars in the format string");
is(strftime("%Y\x{5e74}%m\x{6708}%d\x{65e5}", POSIX::gmtime($jan_16)),
   "1970\x{5e74}01\x{6708}16\x{65e5}",
   "strftime() can handle unicode chars in the format string");

my $ss = chr 223;
unlike($ss, qr/\w/, 'Not internally UTF-8 encoded');
is(ord strftime($ss, CORE::localtime), 223,
   'Format string has correct character');
is(ord strftime($ss, POSIX::localtime(time)),
   223, 'Format string has correct character');
unlike($ss, qr/\w/, 'Still not internally UTF-8 encoded');

setlocale(LC_TIME, $orig_loc) || die "Cannot setlocale() back to orig: $!";

# clock() seems to have different definitions of what it does between POSIX
# and BSD.  Cygwin, Win32, and Linux lean the BSD way.  So, the tests just
# check the basics.
like(clock(), qr/\d*/, "clock() returns a numeric value");
cmp_ok(clock(), '>=', 0, "...and it returns something >= 0");

SKIP: {
    skip "No difftime()", 1 if $Config{d_difftime} ne 'define';
    is(difftime(2, 1), 1, "difftime()");
}

SKIP: {
    skip "No mktime()", 2 if $Config{d_mktime} ne 'define';
    my $time = time();
    is(mktime(CORE::localtime($time)), $time, "mktime()");
    is(mktime(POSIX::localtime($time)), $time, "mktime()");
}