How to convert date to unixtime in perl (or vice versa)

time return number of seconds since 0 in your computer (1 jan 1970) on unix

localtime converts unixtime to normal dates
To convert a specific date to its corresponding unixtime, you use Time::Local, the function looks like this:

$time = timelocal($sec,$min,$hours,$mday,$mon,$year);

so to convert 3rd of Sept 2000 to unixtime, (note that jan=0,feb=1,...):

  use Time::Local;
 $time = timelocal(0,0,0,'3','08','2000');