Unix Time (mtime)?

Question

I have a command line that finds files in a folder and deletes the ones that are a over a day old. I can't seem to find a way/the write code to change the 1 (full) day into a half day (12) hours (f -mtime +1 -exec rm -rf {} ) = older than a day. Do you need to convert into milliseconds and then figure out what a half day is in milliseconds?

Answer 1

This is my query:-
round(oracle_to_unix(to_date(to_char(TDC_CBRN.ANSWER_DT,'YYMMDDHH24MISS'),'YYMMDDHH24MISS')))
The oracle_to_unix function :-
create or replace FUNCTION oracle_to_unix
in_date IN DATE)
RETURN NUMBER
IS
BEGIN
RETURN (in_date -TO_DATE('19700101','yyyymmdd'))*86400 - TO_NUMBER(SUBSTR(TZ_OFFSET(sessiontimezone),1,3))*3600;
END;
is it because of my sessiontimezone ?. if YES.. how could i change it ?
As your information, I am from Malaysia and below is my sessiontimezone on my server.
-- Asia/Taipei