TIL

When you run a script as a systemd service, you have to define its environment variables in the service filem, e.g.

# Set your environment variables here
Environment="OJISAN_INCREMENTAL_UPLOAD_API_KEY=YOUR_ACTUAL_API_KEY_VALUE"
Environment="OJISAN_INCREMENTAL_UPLOAD_DB_USER=your_db_user"
Environment="OJISAN_INCREMENTAL_UPLOAD_DB_PW=your_db_password"
Environment="OJISAN_INCREMENTAL_UPLOAD_DB_NAME=your_db_name"
Environment="DB_HOST=your_db_host"

Show systemd running services as a list

systemctl list-units --type=service --state=running --no-pager

vim: Jump to specific character on a line

In Vim, to jump to a specific character on a line, you can use the following commands:

• f{char} - Jump to the next occurrence of {char} on the current line
• F{char} - Jump to the previous occurrence of {char} on the current line
• t{char} - Jump until (one position before) the next occurrence of {char}
• T{char} - Jump until (one position after) the previous occurrence of {char}

For your specific example of “go to first #”:

• Type f# to jump to the first # character on the current line

Additional tips:

• ; - Repeat the last f, F, t, or T command in the same direction
• , - Repeat the last f, F, t, or T command in the opposite direction

These are extremely useful for quick navigation within a line without having to use arrow keys or other movement commands.

vim: Delete from current cursor position to end of the document

This was not obvious to me (or Claude.ai) - but search turned it up.

vG$d

Explanation

• v enters visual mode
• G moves to the last line of the document
• $ moves to the end of that line
• d deletes everything selected

This combination selects from the current cursor position all the way to the end of the document and then deletes it.

A couple of terms that deal with perceptual distortions and cognitive bias:

• apophenia - a tendency to see connections between two unrelated things.
• pareidolia - the faulty perception of a pattern in an image, e.g. seeing a face in a geologic formation on Mars.

Pareidolia is a specific form of apophenia.

Custom aliases in oh-my-zsh

With oh-my-zsh, you can store custom aliases in multiple (?per application) file under .oh-my-zsh/custom giving them .zsh file extensions.¹

¶For example, in my hugo.zsh file, I have:

alias hnewtil="/Users/alan/Documents/blog/ojisan/scripts/newtil.sh"
alias gtojisan="cd /Users/alan/Documents/blog/ojisan; ls -l;"

Executing inline Python in a shell script

It’s possible using the -c command.²

python -c 'import foo; foo.bar()'

A bunch of Unix date scripting things

Unix shell scripting is not one of my better-know areas of programming, but it’s on my list of things to learn. Some interesting bits about the date function.¹

1. Want the long date, like Thursday, January 28, 2021? → date +"%A, %B %d, %Y"
2. Want something like the above but with abbreviated month Thursday, Jan 28, 2021? → date +"%A, %b %d, %Y"
3. Time zone in the format of "-05:00" on macOS is:

#!/bin/bash

tz=$(date +"%z" | sd '(\d{2})(\d{2})' '$1:$2')
echo $tz

4. Long date in the format of 2021-01-28T05:30:48-05:00 that is use by Hugo²:

tz=$(date +"%z" | sd '(\d{2})(\d{2})' '$1:$2')
md_date=`date +"%Y-%m-%dT%H:%M:%S"`

5. Speaking of dates, this reference has very detailed information on date and time in the Unix shell.
6. Date in the format of 2021-01-28 is date +"%Y-%m-%d"

Unix slurp command output into a variable

In the UNIX shell, slurping the output of the command into a variable is done this way:³

OUTPUT=$(ls -1)
echo "${OUTPUT}"

MULTILINE=$(ls \
   -1)
echo "${MULTILINE}"

Append or overwrite a file in Unix shell

You can either append to a file or overwrite the contents from the shell.⁴

To append to a file, it’s echo "hello" >> file.txt whereas to overwrite the contents of a file, it’s echo "hello" > file.txt

W3schools.com has a CSS library that’s quite nice. I often use Bootstrap; but I like some of the visual features here better. For example, I like their tags because they have more flexible use of colour.

If you want to fetch from a Python dictionary, but you need a default value, this is how you do it:

upos_badge = {'noun': 'lime','verb': 'amber', 'adv': 'blue',}
badge_class_postfix = upos_badge.get(value.lower(), 'light-grey')

I recently learned about DeepL as an alternative to Google Translate. It seems really good.