This will analyse your Pinboard backup to get some statsitcs about what sites are online and link-rot
Log into pinboard.in and go to setting and backups and download your backup as JSON
Rename the file to pinboard.json and put it into the same director as this file
Open the terminal.app and change to the directory that contains this file
Type 'php stats.php > output.csv' and let it run through all the URLs.
This write both to stdout and stderr. You will see the progress of each URL checked on stderr and strout will build-up the csv
When it is complete, it will output some basis stats to the screen.