This week in review: pre-commit hooks

Tue, 07 Jan 2020

Adding a pre-commit hook to automate last modified date update. Pre-commit hooks can do a lot of interesting things.

#!/bin/sh

# https://blog.nerde.pw/2016/08/09/jekyll-last-modified-date.html
echo ************************************
echo *   updating last_modified_at...   *
echo ************************************
git diff --cached --name-status | while read a b; do
  echo * Processing $b...
  sed -i "/---.*/,/---.*/s/^last_modified_at:.*$/last_modified_at: $(date "+%Y-%m-%d %T %z")/" $b
  git add $b
done

Wed, 08 Jan 2020

zero day!

Thu, 09 Jan 2020

Automated planning in a nutshell1. I have been looking into high level Task Planning for robotic systems. The most popular one seems to be the Planning Domain Description language (PDDL). I think I will write more about this later.

TODO: remember to do a writeup on Camera Calibration.▣

Fri, 10 Jan 2020

Copy on Write (CoW): It is when you ask for something to be copied but the program doesn’t immediately copy it, instead will copy it when you try to modify or write the object. Btrfs or B-Tree file system uses CoW.▣

Use UTC time everywhere! I just found a weird bug on my site. Some of the dates on the posts were off by 1. This was caused due to the site being build using UTC time but the dates on the posts and last modified at were in Cali time. I have switched all my scripts to use UTC time now. Time is weird, use UTC.▣

Sat, 11 Jan 2020