Bug #13880 [Com]: date(I) does not correctly identify daylight saving time
| From: | colin dot mutter at gmail dot com | Date: | Fri, 04 Nov 2011 16:30:37 +0000 |
| Subject: | Bug #13880 [Com]: date(I) does not correctly identify daylight saving time | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-164890@lists.php.net to get a copy of this message | ||
Edit report at https://bugs.php.net/bug.php?id=13880&edit=1
ID: 13880
Comment by: colin dot mutter at gmail dot com
Reported by: bmplummer1 at home dot com
Summary: date(I) does not correctly identify daylight saving
time
Status: Bogus
Type: Bug
Package: Date/time related
Operating System: Windows NT/XP
PHP Version: 4.0.6
Block user comment: N
Private report: N
New Comment:
Bradford, yes it's been 10 years, but I thought I should not leave this question
unanswered.
If you ran your test on the 31st (as you mentioned), but just subtracted "1" from
the month, you would have a date like "2001-06-31"; There is no such date, thus
PHP rounds to a real date:
echo date("Y-m-d", strtotime("2001-06-31"));
// => 2001-07-01
Previous Comments:
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[2001-11-01 01:34:05] bmplummer1 at home dot com
cnewbill said this:
Two obvious problems with your test script.
I should be in quotes, and = should be ==. Make those changes and try again.
This works okay on Linux.
-Chris
------------------------------------------------------
First of all...
You are right. I left the quotes out of my bug report. I was, however, using them in the actual
script. If you tested my script you may have also noticed that the following commands return a zero
on a Win32 system when they should return a one:
echo date("I", mktime(0,0,0,5,1,2001));
echo date("I", mktime(0,0,0,6,1,2001));
echo date("I", mktime(0,0,0,7,1,2001));
echo date("I", mktime(0,0,0,8,1,2001));
echo date("I", mktime(0,0,0,9,1,2001));
echo date("I", mktime(0,0,0,10,1,2001));
Also returning a zero instead of a one are:
echo date("I", mktime(0,0,0,date("m")-1,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-2,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-3,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-4,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-5,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-6,date("d"),
date("Y")));
echo date("I", mktime(0,0,0,date("m")-7,date("d"),
date("Y")));
So it doesn't seem to matter how I format the original if/then statement because it will
always evaluate incorrectly because date() is doing something screwy on Win32. Also, I found
something else while working on this. When using the M format, date() has a problem figuring out
what month name it is supposed to return. Here is some example script:
echo date("M, I", mktime(0,0,0,date("m")-1,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-2,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-3,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-4,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-5,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-6,date("d"),
date("Y")));
echo "<br>";
echo date("M, I", mktime(0,0,0,date("m")-7,date("d"),
date("Y")));
That script returns this on my Win32 system:
Oct, 0
Aug, 0
Jul, 0
Jul, 0
May, 0
May, 0
Mar, 0
At least it did for my yesterday (31 Oct 2001). Notice how Jul and May are doubled? What
happened to Apr and Jun?
Could you check in to these issues and let me know what you find out. By the way, thank you for
responding so quickly.
Bradford Plummer
------------------------------------------------------------------------
[2001-10-30 19:36:33] cnewbill@php.net
Works on Windows XP as well with 4.0.6.
-Chris
------------------------------------------------------------------------
[2001-10-30 19:36:28] cnewbill@php.net
Works on Windows XP as well with 4.0.6.
-Chris
------------------------------------------------------------------------
[2001-10-30 19:33:48] cnewbill@php.net
Two obvious problems with your test script.
I should be in quotes, and = should be ==. Make those changes and try again.
This works okay on Linux.
-Chris
------------------------------------------------------------------------
[2001-10-30 19:25:30] bmplummer1 at home dot com
There appears to be a bug in the date() function when using the I (capital i) format. Date(I)
always returns 0 (zero) no matter what the date is. Date(I) is used to determin if a date occurs
during daylight saving time or not. Here is the script I am using:
if (date(I, mktime(0,0,0,6,1,2001))=1) {
do this;
} else {
do that;
}
No mater what the date is it always returns zero. I have tried setting date(I) to a variable
outside of the if/then statement but it always sets the variable to zero. I have tried setting the
timestamp to a variable first and using it in date():
$ts = mktime(0,0,0,6,1,2001);
$ds = date(I, $ts);
That doesn't work either, returns zero. No matter what I do it just doesn't work. Does
this part of date() even work?
Running PHP 4.05 with Zend Optimizer v1.1.0 on Windows NT 4.0 build 1381, CGI version, Apache/1.3.20
. Also doesn't work on PHP 4.06 on Windows XP, CGI version, Apache/1.3.22.
Thank you for your consideration and hard work. PHP is a great product. Keep up the good work!
Bradford Plummer
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Edit this bug report at https://bugs.php.net/bug.php?id=13880&edit=1