Delicious Bookmark this on Delicious Share on Facebook SlashdotSlashdot It! Digg! Digg



PHP : Function Reference : Date and Time Functions : gmmktime

gmmktime

Get Unix timestamp for a GMT date (PHP 4, PHP 5)
int gmmktime ( [int hour [, int minute [, int second [, int month [, int day [, int year [, int is_dst]]]]]]] )

Example 452. gmmktime() on Windows boundary

copy to clipboard
<?php
gmmktime(0, 0, 0, 1, 1, 1970); // valid in GMT and west, invalid in east
?>

Code Examples / Notes » gmmktime

imoore76
Why not just do:
<?php
// assuming $start and $end are timestamps
$day_diff = floor(abs($start - $end) / 86400);
?>

zhong311
When attempting to use HTTP's If-Modified-Since features for caching I ran into the problem of being able to compare the GMT date the browser was sending to my own Last-Modified date (stored in a database field). I saw many examples of how to create a GMT date from a unix timestamp, but little on how to actually get a GMT date into a unix timestamp. Perhaps someone has a better way, here's my solution:
<?php
function gmstrtotime($sgm) {
   $months = array(
     'Jan'=>1,
     'Feb'=>2,
     'Mar'=>3,
     'Apr'=>4,
     'May'=>5,
     'Jun'=>6,
     'Jul'=>7,
     'Aug'=>8,
     'Sep'=>9,
     'Oct'=>10,
     'Nov'=>11,
     'Dec'=>12
   );
   list($D, $d, $M, $Y, $H, $i, $s) = sscanf($sgm, "%3s, %2d %3s %4d %2d:%2d:%2d GMT");
   return gmmktime($H, $i, $s, $months[$M], $d, $Y);
}
// test: after all is said and done
// $time should be the same as $gmtime
$time = time();
$us = date("m/d/Y H:i:s",$time);
$sgm = gmdate("D, d M Y H:i:s",$time) . " GMT";
$gmtime = gmstrtotime($sgm);
echo $us . "
";
echo $sgm . "
";
echo $time . "
";
echo $gmtime . "
";
?>
My results:
02/13/2004 10:45:42
Fri, 13 Feb 2004 20:45:42 GMT
1076705142
1076705142
Credit to kyle at frozenonline dot com for his strtotime example

anzenews
This information is _NOT_ correct:
is_dst
Parameters always represent a GMT date so is_dst doesn't influence the result.
echo gmmktime(1,0,0,3,31,2004); // 1080694800
echo gmmktime(1,0,0,3,31,2004,false); // WRONG: 1080698400
This behaviour is tested on PHP 4.4.4-9, locale sl_SI.

dave
There appears to be a discrepency between PHP and C timestamps.  The C time() and gettimeofday() functions are documented to return based on UTC time, but the value obtained doesn't match the PHP gmmktime() function.  Instead, it matches the PHP mktime() function, which is supposed to be local time.
 
It seems that C always uses a UTC timestamp and adjusts to local time through different handling functions (gmtime() vs localtime()).  PHP appears to use differing UTC/local timestamps, but single handling functions.
The exception to this rule is the PHP time() function, which appears to behave in the same was as the C version.
In short, if your PHP is working with timestamps created in C (or vice versa) make sure you are comparing apples to apples.

dim dot zol
Robert,
Your mismatch is due to the subtraction of date('Y'). You must do an addition instead.
<?php
echo date('Y-m-d H:i:s', time() + intval(date('Z')))."\n";
echo date('Y-m-d H:i:s', gmmktime());
?>
Returns:
2007-07-04 08:03:01
2007-07-04 08:03:01
Take a closer look at the value returned by date('Y') and you will see that anything West of the UTC is negative; hence, it should not be added, not subtracted.

mwwaygoo
REF: http://www.dti.gov.uk/er/sumtimetb.htm
Since 1981 EC Directives have prescribed the start and end dates of summer time in all Member States.  There have to date been eight Directives which have set summer-time arrangements for fixed periods. The Summer Time Act 1972 sets the appropriate dates in the UK and summer-time orders have been made as necessary to implement the European Directives. The 9th EC Directive prescribes the start and end dates of summer time as the last Sundays in March and October respectively. These dates are in line with those already operating in the United Kingdom. The 9th Directive provides that these start and end dates should apply indefinitely.
---
9th EC Directive - 19 January 2001
Article 1
For the purposes of this Directive "summer-time period" shall mean the period of the year during which clocks are put forward by 60 minutes compared with the rest of the year.
Article 2
From 2002 onwards, the summer-time period shall begin, in every Member State, at 1.00 a.m., Greenwich Mean Time, on the last Sunday in March.
Article 3
From 2002 onwards, the summer-time period shall end, in every Member State, at 1.00 a.m., Greenwich Mean Time, on the last Sunday in October.
You stand corrected ;-)  (well up until 2007 anyway)

andy
mwwaygoo's code isn't quite right. My understanding is that the relevant dates for changing between daylight saving time in the UK is the third sunday of march and october - not the last sunday!

francois
In response to mirko at example dot com is_est function, to be exact, the two lines defining $begin_time and $end_time should read:
<?php
$begin_time = gmmktime(1, 0, 0, 3, $begin_date, $Y);
$end_time = gmmktime(1, 0, 0, 10, $end_date, $Y);
?>
Because the clocks go forward, resp. back at 01.00 UTC, not at midnight.

tom
I was getting odd results using gmmktime...
I was converting a date/time to a timestamp to get a date/time in the future. Date/time to convert: Friday 19th of January 2007 10:06:00 PM.
<?php
gmmktime(9, 46, 0, 1 19, 2007);
?>
Returns this timestamp: 1169201160.
When formatted into a GMT date/time it comes out as Friday 19th of January 2007 10:06:00 AM. Notice it's 12 hours out from the original date/time.
I finally found the reason to be that gmmktime needs a 24 time not 12, should of noticed this since it doesn't have an am/pm input.
So the correct call would be something like...
<?php
if($date_time_ampm == "PM") $time_hours += 12;
gmmktime($time_hours, 46, 0, 1 19, 2007);
?>

jbr
I have seen many different hacked versions of this function for people using Windows that want to support dates before Jan 1, 1970. Here is yet another one that is different than others you may have seen! It does not use loops like all the others I have seen!
<?
// usage...
echo win_gmmktime ( 12, 43, 16, 07, 23, 1946 );
function win_gmmktime ( $hour, $minute, $second, $month, $day, $year )
{
if ( $year > 1969 )
{
return ( gmmktime ( $hour, $minute, $second, $month, $day, $year ) );
}
$t = 0;
$ds = 86400;
$hs = 3600;
$dy = 365;
$ms = 60;
$months = array ( 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 );
$leap_year = $year % 4 == 0 && ( $year % 100 > 0 || $year % 400 == 0 ) ? true : false;
if ( $year < 1969 )
{
$y = 1969 - $year;
$t -= ( $y * $dy ) * $ds;
$x = ceil ( $y / 4 );
if ( $leap_year && $month > 2 )
{
$x -= 1;
}
$t -= $x * $ds;
}
if ( $month != 12 )
{
$tm = $months;
$tm = array_slice ( $tm, $month );
$t -= array_sum ( $tm ) * $ds;
unset ( $tm );
}
$nh = ( ( $month == 2 && $leap_year ? 29 : $months[$month-1] ) - $day );
$t -= $nh != 0 ? $nh * $ds : 0;
$nh = 23 - $hour;
$t -= $nh != 0 ? $nh * $hs : 0;
$nh = 59 - $minute;
$t -= $nh != 0 ? $nh * $ms : 0;
$nh = 59 - $second;
$t -= $nh != 0 ? $nh + 1 : 0;
return ( $t );
}
?>

mwwaygoo
I had a problem with hosting a UK site on a US server, the times didnt match (obviously) and also didnt account for daylight savings time. The daylight savings dates and times of change differ worldwide, so detecting if the server was in dst wouldnt work (see http://webexhibits.org/daylightsaving/).
Here is a function for creating a timestamp which can be used by date() to create all the parameters required to display the local time (site not server). I have used GMT time to create the timestamp as there is no offset for UK time (+00).
<?php
function UKdst_time()
{
// created by Matthew Waygood (www.waygoodstuff.co.uk)
$timestamp = mktime(gmdate("H, i, s, m, d, Y")); // UTC time
$this_year=gmdate("Y", $timestamp);
// last sunday in march at 1am UTC
$last_day_of_march=gmmktime(1,0,0,3,31,$this_year);
$last_sunday_of_march=strtotime("-".gmdate("w", $last_day_of_march)." day", $last_day_of_march);

// last sunday in october at 1am UTC
$last_day_of_october=gmmktime(1,0,0,10,31,$this_year);
$last_sunday_of_october=strtotime("-".gmdate("w", $last_day_of_october)." day", $last_day_of_october);
if( ($timestamp > $last_sunday_of_march) && ($timestamp < $last_sunday_of_october) )
{
$timestamp=$timestamp+3600; // foward one hour
}
return $timestamp;
}
?>

justin
Here's a play on turgut85's countDays function.  I've found it to be more efficient and it accepts unix timestamps rather than arrays.  Thanks for the ideas.
function count_days($start, $end) {
 // Count the days between $start and $end where both $start and $end
 //  are UNIX timestamps
 
 // Swap the two values if end is greater than start (to avoid the
 //  loop of death).
 if ($start < $end) {
   $t = $start;
   $start = $end;
   $end = $t;
 }
 
 // Increment the start time by one day until it is equal to the
 //  end time
 
 $days = 0;
 while ( $start < $end ) {
   $start = strtotime("+1 days", $start);
   $days++;
 }
 
 return $days;
}

welch
Here is a handy routine for counting down to the minute, hour, and day to a timestamp
     $minutesleft = floor(($timestamp - gmtime()) / 60);
     if ($minutesleft < 0) {
       $timeleft = 'NOW';
     }
     else if ($minutesleft < 60) {
       $timeleft = ($minutesleft==1 ? '1 minute' : $minutesleft.' minutes');
     }
     else if ($minutesleft >= 60 && $minutesleft < (24*60)) {
       $timeleft = (floor($minutesleft/60) == 1 ? '1 hour' : floor($minutesleft/60).' hours');
     }
     else if ($minutesleft >= (24*60)) {
       $days = floor($minutesleft / (24*60));
       // hours remainder
       $hours = ($minutesleft % (24*60)) / 60;
       // hours left in the day
       $hours_left = ((time() / 60) % (24*60)) / 60;
       // see if the remainder of hours is greater than the hours left in today, if so increase the days by one so that the days remaining mimics the date rather than how many 24 hour periods there are between now and then.
       if($hours > $hours_left) {
         $days++;
       }
       $timeleft = ($days == 1 ? '1 day' : $days.' days');
     }
     echo $timeleft;

phpcoder
gmmktime() should ONLY be used to create a timestamp when specifying a specific GMT date and time.
If you want to make a valid time stamp for the current date & time, use mktime() instead.
UNIX timestamps, by definition, store the GMT time relative to the UNIX epoch.
gmmktime() (without any parameters specified) will effectively use the computer's LOCAL time values just the same as if they were explicit parameters, and the resulting time stamp will be incorrect.  (The resulting timestamp will actually be offset in the OPPOSITE direction of the local timezone offset from GMT!)

15-sep-2005 05:02
function getTimeRemaining($timeZonePass,
$dateTimeUser,$ID,$table,$coloumnName)
{
global $configVars;
$timeZoneDefault=explode("_",$timeZonePass);
$timeZone=(substr($timeZoneDefault[0],1))*(60) ;
if((substr($timeZoneDefault[0],0,1)) =="+")
$defaultSeconds=gmdate("Y-m-d-H-i-s",time()+
$timeZone);
elseif((substr($timeZoneDefault[0],0,1)) =="-")
$defaultSeconds=gmdate("Y-m-d-H-i-s",time()-
$timeZone);
else
$defaultSeconds=gmdate("Y-m-d-H-i-s",time());
$defaultSecondsExp=explode("-",$defaultSeconds);
$defaultGmktime=gmmktime($defaultSecondsExp[3],
$defaultSecondsExp[4],
$defaultSecondsExp[5], $defaultSecondsExp[1],
$defaultSecondsExp[2],
$defaultSecondsExp[0]);
$dateArray=explode("-",$dateTimeUser);
$slectedGmktime=gmmktime(23,59,59,$dateArray[1],
$dateArray[2],$dateArray[0]);
if((substr($timeZoneDefault[0],0,1)) =="+")
$slectedGmktimeAdded=($slectedGmktime)+
($timeZone);
elseif((substr($timeZoneDefault[0],0,1)) =="-")
$slectedGmktimeAdded=($slectedGmktime)+
($timeZone);
else
$slectedGmktimeAdded=($slectedGmktime);
//$slectedGmDate=gmdate("Y-m-d-H-i-s",
$slectedGmktimeAdded);
$timeMinus=$slectedGmktimeAdded -
$defaultGmktime;
$secondsInDay= 60*60*24;
if ($secondsInDay <= $timeMinus)
{
$daysRemaining = floor($timeMinus/
$secondsInDay);
if($daysRemaining >1 )
return $daysRemaining ."&nbsp;Days&nbsp;";
else
return $daysRemaining ."&nbsp;Day&nbsp;";
}
if(empty($daysRemaining))
{
$secondsInHour= 60*60;
if ($secondsInHour <= $timeMinus)
{
$hoursRemaining =floor ($timeMinus/
$secondsInHour);
if($hoursRemaining > 1 )
return $hoursRemaining ."&nbsp;Hours&nbsp;";
else
return $hoursRemaining ."&nbsp;Hour&nbsp;";
}
}
if(empty($hoursRemaining))
{
//$secondsRemaining = $timeMinus. "&nbsp;Seconds";
$secondsInMinute = 60;
if ($secondsInMinute <= $timeMinus)
{
$mintuesRemaining =floor ($timeMinus/
$secondsInMinute);
if($mintuesRemaining > 1 )
return $mintuesRemaining ."&nbsp;Minutes&nbsp;";
else
return $mintuesRemaining ."&nbsp;Minute&nbsp;";
}
}
if(empty($mintuesRemaining))
{
$secondsRemaining = $timeMinus;
if($secondsRemaining < 0)
{
timedOutSale($ID,$table,$coloumnName);
return "Time out";
}
elseif($secondsRemaining > 1 )
return $secondsRemaining . "&nbsp;Seconds";
else
return $secondsRemaining . "&nbsp;Second";
}
}
function timedOutSale($ID,$table)
{
GLOBAL $configVars, $db,$tableNames;
$query =  "UPDATE " . $table
. " SET status = 'T'
WHERE $coloumnName = '" . $ID ."'";
$result = $db->query($query);
return;
}

robert chapin
dim dot zol:
Check your clocks sir ;)  time() returns the local clock under PHP 4, so the mistake is addition.  If gmmktime() is adding the offset to local time then it is officially broken.
Example:
Program run at 09:52 zulu
echo date('Y-m-d H:i:s', time() - intval(date('Z'))).'<br />';
echo date('Y-m-d H:i:s', gmmktime());
echo date('Y-m-d H:i:s', time() + intval(date('Z'))).'<br />';
echo date('Y-m-d H:i:s', gmmktime());
Results:
2007-07-08 09:52:22
2007-07-07 21:52:22
2007-07-07 21:52:57
2007-07-07 21:52:57
Robert Chapin
Chapin Information Services

moshe dot ortov
Beware that despite the documentation which states is_dst is ignored, with PHP 5.2 at least, it is not actually ignored and will cause a 1 hour offset on the UTC time returned.
This caused some interesting bugs, especially with the tzdelta function shown from previous posts below - you need to make the final parameter a 0 instead of $ar[8] otherwise you get an off-by-1-hour as a result.
As a result, I now use :
function tzdelta ( $iTime = 0 ) {
       if ( 0 == $iTime ) { $iTime = time(); }
       $ar = localtime ( $iTime );
       $ar[5] += 1900; $ar[4]++;
       $iTztime = gmmktime ( $ar[2], $ar[1], $ar[0], $ar[4], $ar[3], $ar[5], 0);
       return ( $iTztime - $iTime );
}

robert chapin
Behavior seen in PHP 4:
<?php
echo date('Y-m-d H:i:s', time() - intval(date('Z'))).'<br />';
echo date('Y-m-d H:i:s', gmmktime());
?>
Output:
2007-07-03 00:25:51
2007-07-02 12:25:51
The first result is correct.  I do not yet know the cause of this problem.

francois
A simpler way to get a GMT date into a UNIX timestamp is to use the strtotime() function.
<?php
// Prints: 1076705142
$gmstr = 'Fri, 13 Feb 2004 20:45:42 GMT';
echo strtotime($gmstr);
?>

tom
@ Robert Chapin
You have the same problem as I did, gmmktime requires the hours to be in the 24 hour format.
See my post below.

ranjeet
<?php
function getTimeRemaining($timeZonePass,
$dateTimeUser,$ID,$table,$coloumnName)
{
global $configVars;
$timeZoneDefault=explode("_",$timeZonePass);
$timeZone=(substr($timeZoneDefault[0],1))*(60) ;
if((substr($timeZoneDefault[0],0,1)) =="+")
  $defaultSeconds=gmdate("Y-m-d-H-i-s",time()+
  $timeZone);
elseif((substr($timeZoneDefault[0],0,1)) =="-")
  $defaultSeconds=gmdate("Y-m-d-H-i-s",time()-
  $timeZone);
else
  $defaultSeconds=gmdate("Y-m-d-H-i-s",time());
$defaultSecondsExp=explode("-",$defaultSeconds);
$defaultGmktime=gmmktime($defaultSecondsExp[3],
          $defaultSecondsExp[4],
$defaultSecondsExp[5], $defaultSecondsExp[1],
          $defaultSecondsExp[2],
$defaultSecondsExp[0]);
$dateArray=explode("-",$dateTimeUser);
$slectedGmktime=gmmktime(23,59,59,$dateArray[1],
          $dateArray[2],$dateArray[0]);
if((substr($timeZoneDefault[0],0,1)) =="+")
  $slectedGmktimeAdded=($slectedGmktime)+
                      ($timeZone);
elseif((substr($timeZoneDefault[0],0,1)) =="-")
  $slectedGmktimeAdded=($slectedGmktime)+
                      ($timeZone);
else
  $slectedGmktimeAdded=($slectedGmktime);
//$slectedGmDate=gmdate("Y-m-d-H-i-s",
          $slectedGmktimeAdded);
$timeMinus=$slectedGmktimeAdded -
      $defaultGmktime;
$secondsInDay= 60*60*24;
if ($secondsInDay <= $timeMinus)
{
  $daysRemaining = floor($timeMinus/
                  $secondsInDay);
  if($daysRemaining >1 )
      return $daysRemaining ."&nbsp;Days&nbsp;";
  else
      return $daysRemaining ."&nbsp;Day&nbsp;";
}
if(empty($daysRemaining))
{  
  $secondsInHour= 60*60;
  if ($secondsInHour <= $timeMinus)
  {
      $hoursRemaining =floor ($timeMinus/
                      $secondsInHour);
      if($hoursRemaining > 1 )
          return $hoursRemaining ."&nbsp;Hours&nbsp;";
      else
          return $hoursRemaining ."&nbsp;Hour&nbsp;";
  }
}
if(empty($hoursRemaining))
{
  //$secondsRemaining = $timeMinus. "&nbsp;Seconds";
  $secondsInMinute = 60;
  if ($secondsInMinute <= $timeMinus)
  {
      $mintuesRemaining =floor ($timeMinus/
              $secondsInMinute);
      if($mintuesRemaining > 1 )
          return $mintuesRemaining ."&nbsp;Minutes&nbsp;";
      else
          return $mintuesRemaining ."&nbsp;Minute&nbsp;";
  }
}
if(empty($mintuesRemaining))
{
  $secondsRemaining = $timeMinus;
  if($secondsRemaining < 0)
  {  
      timedOutSale($ID,$table,$coloumnName);
      return "Time out";
  }
  elseif($secondsRemaining > 1 )
      return $secondsRemaining . "&nbsp;Seconds";
  else
      return $secondsRemaining . "&nbsp;Second";
}
}
function timedOutSale($ID,$table)
{
  GLOBAL $configVars, $db,$tableNames;
  $query =  "UPDATE " . $table
                  . " SET status = 'T'
                  WHERE $coloumnName = '" . $ID ."'";
          $result = $db->query($query);
  return;
}
?>

turgut85
<?php
// THIS ROUTINE COUNT DAYS BEETWEEN TWO DATE //
// BEGIN DATE COULD BE IN THE PAST OR IN THE FUTURE //
$beg['YEAR']=2004;
$beg['MONTH']=10;
$beg['DAY']=1;
$end['YEAR']=2004;
$end['MONTH']=10;
$end['DAY']=3;
function countDays ($beg,$end) {

$start = gmmktime(0,0,0,$beg['MONTH'],$beg['DAY'],$beg['YEAR']);
$endin = gmmktime(0,0,0,$end['MONTH'],$end['DAY'],$end['YEAR']);
// echo $start."\n";
// echo $endin."\n";
$day = 0;
if ($start < $endin) {
$toward = 1;
} else  {
$toward = 0;
}
$mover = $start;
if ($start != $endin) {

do {

$day++;

if ($toward)  {
$mover = gmmktime(0,0,0,$beg['MONTH'],($beg['DAY']+$day),$beg['YEAR']);
} else {
$mover = gmmktime(0,0,0,$beg['MONTH'],($beg['DAY']-$day),$beg['YEAR']);
}

} while ($mover != $endin);
}
echo $day;
return $day;
}
echo countDays ($beg,$end). " days. ";
?>
Turgut Z. YESILYURT
turgut85@hotmail.com
System and Application Developer
New Jersey, USA

mirko
<?php
/**
* Check if given time is during Europen Summer Time
*
* @link http://en.wikipedia.org/wiki/European_Summer_Time
* @param int $time UTC timestamp (GMT)
* @return boolean true if it is EST else false
*/
function is_est($time)
{
   // get year
   $Y = gmdate("Y", $time);
   
   // calc start / end dates and time for that year
   $begin_date = (31 - (5*$Y/4 + 4) % 7);
   $end_date = (31 - (5*$Y/4 + 1) % 7);
   $begin_time = gmmktime(0,0,0,  3,$begin_date,$Y);
   $end_time = gmmktime(0,0,0,  10,$end_date,$Y);
   
   // if it's in that period
   $is_dst = $time >= $begin_time && $time < $end_time;
   return $is_dst;
}
?>

Change Language


Follow Navioo On Twitter
checkdate
date_create
date_date_set
date_default_timezone_get
date_default_timezone_set
date_format
date_isodate_set
date_modify
date_offset_get
date_parse
date_sun_info
date_sunrise
date_sunset
date_time_set
date_timezone_get
date_timezone_set
date
getdate
gettimeofday
gmdate
gmmktime
gmstrftime
idate
localtime
microtime
mktime
strftime
strptime
strtotime
time
timezone_abbreviations_list
timezone_identifiers_list
timezone_name_from_abbr
timezone_name_get
timezone_offset_get
timezone_open
timezone_transitions_get
Terms of Service Privacy Policy Sitemap

©2024 -EPSILONSYS SOFTWARE inc

Other EPSILONSYS SOFTWARE Web Sites : Programming Resources | News Headline | Free local classifieds

eXTReMe Tracker