From a3eb6de4044adfbd91e6a55dade03fab2547ba84 Mon Sep 17 00:00:00 2001 From: Kévin Le Gouguec Date: Tue, 3 Dec 2019 22:20:41 +0100 Subject: Add introductory guide to shells --- guides/shell-101.org | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 guides/shell-101.org (limited to 'guides') diff --git a/guides/shell-101.org b/guides/shell-101.org new file mode 100644 index 0000000..b09118b --- /dev/null +++ b/guides/shell-101.org @@ -0,0 +1,44 @@ +My tentative introductory guide to navigating a shell interface +(assuming Bash). + +🚧 These are rough notes meant for guiding in-person discussions; they +are somewhat terse. 🚧 + +* Moving around, invoking stuff + +With a file browser and a terminal emulator side-by-side: + +- ls, cd, mkdir, touch, rm; "/" = root +- globs +- arguments vs options (e.g. ls, diff) +- man, --help +- standard input/output/error: pipes, redirection +- writing scripts (shebangs: see bash(1) § COMMAND EXECUTION) + +* Shell language + +- ; & (e.g. sleep) +- && || (e.g. grep) +- if, for +- $? (e.g. grep, diff) +- [ +- variables +- functions, $@, $1… +- black-box model of a command: + - inputs: stdin, arguments, environment + - outputs: stdout, stderr, exit code + - side-effects: writing files, connect to network, … +- which, type: keyword ≠ builtin ≠ function ≠ program +- valar quotulis (valar escaepis); e.g. sort operator: [ foo '>' bar ] + +* Advanced + +- ( ) ≠ { }: try to set variables, or call exit +- (( )), $( ) +- glob ≠ regex +- bash extensions + - [[ + - <( ) + - |&, >& + - arrays +- job control: fg, bg, jobs, wait, kill, C-z -- cgit v1.2.3