title: adding 30 minutes to datetime php/mysql
body: <p>I have a datetime field (endTime) in mysql. I use gmdate() to populate this endTime field.</p>
  
  <p>The value stored is something like 2009-09-17 04:10:48.   I want to add 30 minutes to this endtime and compare it with current time. ie) the user is allowed to do a certain task only 30 minutes within his endTime. After 30 minutes of his endTime, i should not allow him to do a task.</p>
  
  <p>how can i do that in php?</p>
  
  <p>i'm using gmdate to make sure there are no zone differences.</p>
  
  <p>Thanks in advance</p>