What is Hackers' Pub?
Hackers' Pub is a place for software engineers to share their knowledge and experience with each other. It's also an ActivityPub-enabled social network, so you can follow your favorite hackers in the fediverse and get their latest posts in your feed.

![### there are lots of Unix shells
- dash
- bash
- sh
- zsh
- fish
- csh
- tcsh
- ksh
you can find out your user's default shell by running:
`$ echo $SHELL`
### POSIX is a standard that defines how Unix shells should work
sh, dash, bash, zsh, and ksh, all represented by little boxes with smiley faces: if your script sticks to POSIX, we'll all run it the same way! (mostly [smiley face])
fish: I don't care about POSIX
### some shells have extra features
bash, zsh, and ksh: we have extra features that aren't in POSIX
sh and dash: we keep it simple & just do what POSIX says
### on most systems, /bin/sh only supports POSIX features
smiling stick figure with short curly hair: if your script has `#!/bin/sh` at the top, don't use bash-only features in it!
### some people write all their scripts to follow POSIX
smiling stick figure with straight chin length hair: I only use POSIX features
smiling stick figure with short curly hair, labelled "me": I use lots of bash-only features!
### this zine is about bash scripting
smiling stick figure with short curly hair: most things in this zine will work in any shell, but some won't! page 15 lists some non-POSIX features](https://cdn.masto.host/socialjvnsca/media_attachments/files/116/268/572/489/858/064/original/7d8ad2dd12a3937a.png)
















一般 Kyungmi Ahn ꉂꉂ(ᴖᗜᴖ*) 








