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Difference between two Timestamps

Difference between two Timestamps

Difference between two Timestamps

Hello everyone,

using ksh I need to figure out how many days have passed between a timestamp and the current date of today.

Format of the timestamp is:

YYYYMMDD (e.G. 20200703)



date +%Y%m%d 

will give me the correct format for the current date and at first sight simply substracting both is working fine as long as both are within the same month ...



20200716 - 20200703 

Problem is obvious:


20200801 - 20200703 

Any ideas how to solve this ?

Best Regards,

RE: Difference between two Timestamps


Such math is usually done with Unix times :

CODE --> Ksh

echo $(( ($( date +'%s' ) - $( date -d "$date" +'%s' )) / 24 / 60 / 60 )) 


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