Shell Programming and Scripting

Hello eveyone, I am tasked to write an (n)awk script to calculate the days between dates. Now before anyone chastizes me on how many forums there are on date calculation, I have no seen one that takes into account the Julian calender as well. As most know, September of 1752 is when we (the US) adopted the Gregorian calender and when you "cal 9 1752" you will note 11 days missing. Here is my question or questions. If I plug in a date before 1752 and one after 1752 should my algorithm be 11 days off?

That is where I am having a problem. I am not really sure as to how to start my algorithm. Can anyone help with this. I do not want anyone to write the script, just help me with the algorithm.

I'm not an expert, but from what I've read you need to

a) explicitly exclude September 3-13 (inclusive) 1752 if basing your calendar on the US conversion.

b) Take into account that leap years prior to, and including, 1752 did not exclude century years that weren't divisible by 400 as are done with the Gregorian calendar. For example 1500 was a leap year and had 366 days.

how about to calculate by epoc time

Code:

bash-3.00$ date -d "sep 11 1975" +%s
1315736100
bash-3.00$ date -d "sep 2 1975" +%s
1314958500
bash-3.00$ date -d "sep 14 1975" +%s
1315995300