Uly.me

cloud engineer

Archives for November 2022

Open Browser in Bash

Here’s a nice little command to open a browser from Bash.

#!/bin/bash
open https://domain.com/path/to/web/page/index.html

You can use this command to open a web page from your script.

Bash Any Key

Here’s the script to add pauses in your Bash script.

echo "please wait until web page loads ... "
read -p "Press any key to continue... " -n1 -s

You can also put it inside a function and call it multiple times.

function press_any_key {
  echo "please wait until web page loads ... "
  read -p "Press any key to continue... " -n1 -s
}
press_any_key

Crontab on macOS Monterey

A recent OS upgrade rendered the crontab to malfunction on macOS Monterey. It turned out the system just needed a reset of System Preferences > Security & Privacy > Privacy tab, and to make sure cron has full access to disks. Once you flipped that, your crontab should start working. Hope that helps.

Crop Factor Calculator

If you’re into photography, you would know what crop factor means. I have a Nikon D90 camera with a crop factor of 1.5. For example, if you use a 24mm full frame lens on a D90, the focal length will be 36mm. So, here’s a handy bash script that calculates the crop factor by multiplying the full frame focal length by 1.5.

#!/bin/bash
if [ $# -eq 0 ]
  then
    echo "Usage: cropfactor.sh 24"
    exit
fi
a=$(echo "1.5 * $1" | bc)
echo "Cropfactor focal length is: " $a"mm."

Result

ulysses@penguin:~/Code$ ./cropfactor.sh 24
Cropfactor focal length is:  36.0mm.