Do timestamps only go back to 1970?

bunner_bob

Reading through the PHP manual about timestamps, I came across this phrase

On windows this range is limited from 01-01-1970 to 19-01-2038.

I have a number of functions that reformat dates stored in MySQL format (YYYY-MM-DD) - for instance

$date = date('n/j/Y', strtotime($myrow["date"]));

When I feed it a date in 1902 or later it seems to work fine. If I feed it a date in 1901 it changes it to December 31, 1969. I'm running a Mac (OS X), but I wonder what my Windows users are encountering?

I'm surprised this seemingly core component is so limited in the date range it will represent. Are there some standard workarounds for dealing with broader date ranges, other than just checking to make sure all functions used don't use timestamps?

I'm not seeking an answer to a specific question here, just a better understanding of how other programmers deal with this issue. My current application fortunately is unlikely to need dates before 1970, but I have no doubt I will have need for such in the future.

Thanks!

barand

The mySql 'DATE' type holds dates from 1000-01-01 to 9999-31-12

bunner_bob

Yes - I do realize MySQL's date format is much broader. It's too bad so many of PHP's date functions use the Unix timestamp as their basis - for instance, the date() function for formatting a timestamp in a user-friendly format, as well as strtotime(), mktime() and gmdate().

I will have to evaluate each of my date instances to determine whether it's more important to have user-friendliness or a broad date range.

Maybe the next version of PHP will address this.

barand

It can be a pain!

I've had to resort to workarounds like this just to calculate my own age (or that of anyone else over 32)

function age($d,$m,$y) {
  $ydiff = 1969 - $y;
  $bd = mktime(0,0,0,$m,$d,1970);
  $bdarray = getdate($bd);
  $nowarray = getdate(time());
  if ($bdarray["yday"] < $nowarray["yday"]) $ydiff++;
  return $ydiff + date("Y") - date("Y",$bd);
}