42 School project with @Lucie-Kin and @LycorisDev based on Bash 3.
It is customary to name one's shell, and we chose bigerrno. It is a pun mixing the French word bigorneau, which is a seashell, and the idea of a big mistake with "big" and "errno", aka "error number".
Environment
- variable lists: environment, hidden environment and local vars
- environment: set a few vital variables when the environment is empty on shell startup
- expand
$$(PID),$0(argv[0]) and environment variables in shell and also in heredoc if not delimiter - expand tilde
~,~+and~- - increment SHLVL when opening a shell (yes we have the list of shells), and decrement within a command (e.g.
env | grep SHLVL)
Builtins
- echo = on top of
-n,-eand no option - cd = on top of a relative or absolute path,
-and no option - export = also append option
a += b - handle Schrödinger paths:
mkdir dir1 && cd dir1 && mkdir dir2 && cd dir2 && rm -rf ../../dir1
History
- add heredoc to history
Parsing
- backslash to concatenate two lines in shell and heredocs
- backslash to escape characters
- interpret special characters in
$'string'and "echo -e", including Unicode sequences (e.g.: 🐚 $'\U1F41A') - multi-line input (see it by copy-pasting several lines at once)
- prompt for more input in case of unclosed quote
Wildcard
- expand asterisk wildcards with any path given, not just the current directory (still no subdirectory)
Signals
- output the correct flavor text when an external command terminates from a signal
Aesthetic
- prompt: identical to bash
user@host:path$even with an empty environment - colors: Ubuntu GNOME themed text and background
- window title: 🐚 set to the prompt 🐚
- opening a shell: reset the background color and window title
- lulu = change of terminal background and prompt colors
- matrix = green random letters with black background raining down the screen
- disco = annoying endless call of lulu in an epileptic non-friendly fashion