Date Quartet Mac OS

Syntax date -nu -r seconds +format ccyymmddhhmm.ss Options -n The utility timed (8) is used to synchronize the clocks on groups of machines. By default, if timed is running, date will set the time on all of the machines in the local group. Convert Mac HFS+ timestamp (seconds since 1904) to human-readable date. This script converts Apple Mac OS X HFS+ timestamps to normal dates. An HFS Plus-timestamp is the number of seconds since midnight, January 1, 1904, GMT. These timestamps are also used by Apple iPod's, Palm OS, JMP/JSL datetime and others. The current Mac timestamp is.

Mac OS 8.1 is an operating system that was designed and developed by Apple in 1998 alongside Apple’s Macintosh computers. This operating system has been released on 19 January 1998 and its price started at $99. The new Mac OS 8.1 features a new file system named HFS+ and Mac OS Extended, integrated Internet Explorer, Java support, greater performance and efficiency, up to 50% faster application launch and relaunch, expanded support for PC files and media, and much more. This version of Mac OS has been replaced by Mac OS 8.5.

Today Mac OS 8.1 is 23 years old!

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Mac OS 8.1 – General information

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Date Quartet Mac OS

Date Quartet Mac Os Catalina

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I dont understand why this command gives an error:
date -j -f '%Y%m%d%H%M%S' '20091101201023' '+%s'
Failed conversion of ``20091101201023' using format ``%Y%m%d%H%M%S'
date: illegal time format
usage: date [-jnu] [-d dst] [-r seconds] [-t west] [-v[+ -]val[ymwdHMS]] ...
[-f fmt date [[[mm]dd]HH]MM[[cc]yy][.ss]] [+format]
But this i ok:
date -j -f '%Y %m %d %H %M %S' '2009 11 01 20 10 23' '+%s'
1257106223
The commands in Mac Os X are a bit different than in Linux that im am used to. Makes it somewhat difficult to script in the shell.
20091101201023 is the format of the date that i get from a file and i want to convert it in a script to seconds since epoc among other things.
Is it possible with the date command? Or is there some replacement for the date command in the terminal?