Identical to the date() function except that
the time returned is Greenwich Mean Time (GMT). For example, when
run in Finland (GMT +0200), the first line below prints "Jan 01
1998 00:00:00", while the second prints "Dec 31 1997 22:00:00".
Example 1. gmdate() example
echo date ("M d Y H:i:s", mktime (0,0,0,1,1,1998));
echo gmdate ("M d Y H:i:s", mktime (0,0,0,1,1,1998));