how to pass calculate date to bash shell?

Question

I have this test.sh

#!/bin/bash echo $1

calling it works:

sh ./test.sh $(date +"%F")

I want to subtract 5 days from current date and pass to test.sh

sh ./test.sh $(date --date="date-5 day" +"%F")

The line above does not work. What is the correct way?

You're trying to do something that can't be done without being way more specific, and is kind of @jon-skeet's domain: what does "minus 5 days" mean. Is it 120 hours? In which timezone? Following which calendar? In which locale? Things get rather complicated even if you "just want 5 days ago", because there is no "just" when it comes to date/time calculations. So instead of asking bash for this information, use a date/time CLI utility, or a proper date/time library from a scripting language with a solid enough such library that you can trust the results to be right. — Mike 'Pomax' Kamermans
– Mike 'Pomax' Kamermans, Commented Aug 9, 2017 at 3:39

Cyrus · Accepted Answer · 2017-08-09 05:41:44Z

1

I suggest:

sh ./test.sh $(date --date="-5 day" +"%F")

With my settings en_US.UTF-8 command date --date="-5 day" +"%F" outputs 2017-08-04.

answered Aug 9, 2017 at 5:36

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