"$bash" by "Andrew Mager" on Flickr

One to read: Put your bash code in functions

I’ve got a few mildly ropey bash scripts which I could do with making a bit more resilient, and perhaps even operating faster ;)

As such, I found this page really interesting: https://ricardoanderegg.com/posts/bash_wrap_functions/

In it, Ricardo introduces me to two things which are interesting.

  1. Using the wait command literally waits for all the backgrounded tasks to finish.
  2. Running bash commands like this: function1 & function2 & function3 should run all three processes in parallel. To be honest, I’d always usually do it like this:
    function1 &
    function2 &
    function3 &

The other thing which Ricardo links to is a page suggesting that if you’re downloading a bash script and executing it (which, you know, probably isn’t a good idea at the best of times), then wrapping it in a function, like this:

#!/bin/bash

function main() {
  echo "Some function"
}

main

This means that the bash scripting engine needs to download and parse all the functions before it can run the script. As a result, you’re less likely to get a broken run of your script, because imagine it only got as far as:

#!/bin/bash
echo "Some fun

Then it wouldn’t have terminated the echo command (as an example)…

Anyway, some great tricks here! Love it!

Featured image is “$bash” by “Andrew Mager” on Flickr and is released under a CC-BY-SA license.

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