The general way to do "time math" is to convert to epoch seconds, do math in seconds and then convert back to a string.

Except it doesn't work. Not all days have 24*60*60 seconds.

the OP's idea of adding zero is a GREAT idea.

And POSIX's strftime is the way to do it if you're already dealing with localtime or gmtime (It handles the y+1900 and the m+1 for you.) 

use POSIX qw( strftime );
print( strftime('%Y%m%d', localtime), "\n");

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In reply to Re^2: Date Time problem. by ikegami
in thread Date Time problem. by Karger78

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