Friday 21 April 2023

Today I Learned - Munging Epochs using awk

So today I had a requirement to convert some Epoch-formatted dates, located in a CSV file, into human-readable dates...

So today I learned about awk vs. gawk, and the strftime() function ...

I also learned that awk on macOS isn't the same as "real" Gnu awk ( aka gawk ), hence the need for gawk ...

I started by installing gawk: -

brew install gawk

and then updated my PATH to reflect it: -


Using an example of my data: -

cat file.txt


which is WAY simpler than my real data, I was then able to munge it using awk ( or, really, gawk ) : -

awk 'BEGIN { FS = ","} ; {$1 = strftime("%c", $1)} 1' file.txt

which returns: -

Fri 14 Apr 16:35:14 2023
Thu 20 Apr 12:39:47 2023
Thu 20 Apr 13:14:13 2023
Mon 17 Apr 07:29:09 2023

I'd previously done much the same using Excel, via a formula: -


where cell F17 contained the Epoch-formatted date

But scripts are so much more fun ...

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Visual Studio Code - Wow 🙀

Why did I not know that I can merely hit [cmd] [p]  to bring up a search box allowing me to search my project e.g. a repo cloned from GitHub...