Update README to reflect current feature set and installer

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

README.md

@@ -1,60 +1,117 @@
 # bash-for-windows
 
-A fully functional bash shell for Windows, written in Go. Run bash commands and scripts natively on Windows without WSL, Cygwin, or MSYS2.
+A bash-compatible shell for Windows, written in Go. Runs natively as a single `.exe` — no WSL, Cygwin, or MSYS2 required.
+
+## Install
+
+1. Download the latest release zip and extract it.
+2. Double-click **`install.bat`**.
+
+That's it. The installer:
+- Copies `bash.exe` to `%LOCALAPPDATA%\Programs\BashForWindows\`
+- Adds it to your user **PATH**
+- Registers a **"Bash for Windows"** profile in Windows Terminal so it shows up in the `+` dropdown
+
+```powershell
+# Optional flags
+.\install.ps1 -InstallDir "C:\Tools\bash"   # custom install path
+.\install.ps1 -NoTerminal                   # skip Windows Terminal profile
+.\install.ps1 -Uninstall                    # clean removal
+```
 
 ## Features
 
-- **Interactive shell** with prompt (`bash$`)
-- **Built-in commands**: cd, pwd, echo, exit, export, source, alias, type
-- **Built-in coreutils**: ls, cat, grep, sort, wc, head, find, cp, mv, rm, mkdir, touch, clear
-- **Command chaining**: `&&`, `||`, `;`
-- **Pipes**: `|` between commands
-- **Variable expansion**: `$NAME`, `${NAME}`
-- **Variable assignment**: `NAME=VALUE command`
-- **Single & double quotes**: `'literal'`, `"$variable"`
-- **Script execution**: `bash-windows script.sh` or `-c 'commands'`
-- **No dependencies** — single `.exe` file, runs on any Windows x86-64
+### Shell language
+- **Control flow** — `if/elif/else/fi`, `for/do/done`, `while/until`
+- **Functions** — `name() { ... }` and `function name { ... }`, with `local`/`return`
+- **Arithmetic** — `$(( expr ))`, `$((i + 1))`, `$((n % 2))`
+- **Command substitution** — `$(cmd)`, including pipelines: `x=$(echo foo | tr a-z A-Z)`
+- **Variable expansion** — `$VAR`, `${VAR}`, `${VAR:-default}`, `${VAR:=val}`, `${#VAR}`, `${VAR%suffix}`, `${VAR#prefix}`
+- **Glob expansion** — `*.txt`, `src/**`
+- **Tilde expansion** — `~/Documents`
+- **Quotes** — single `'literal'`, double `"with $vars"`, backslash escapes
+- **Inline comments** — `echo hello  # this is ignored`
+
+### I/O
+- **Pipelines** — `cmd1 | cmd2 | cmd3`
+- **Redirection** — `>`, `>>`, `<`, `2>`, `2>&1`, `&>`
+- **Background jobs** — `cmd &`
+- **Command chaining** — `&&`, `||`, `;`
+
+### Interactive
+- **Command history** with arrow keys (saved to `~/.bash_history`)
+- **Tab completion** for commands and file paths
+- **Multi-line input** — `if`/`for`/`while`/functions continue on the next line
+- **Prompt** shows current directory and last exit code when non-zero
+
+### Built-in commands
+| Category | Commands |
+|----------|----------|
+| Shell | `cd`, `pwd`, `echo`, `exit`, `export`, `set`, `unset`, `source`/`.`, `alias`, `unalias`, `type`, `command`, `which`, `env` |
+| Control | `true`, `false`, `test`/`[`, `break`, `continue`, `return`, `shift`, `read`, `printf` |
+| Variables | `declare`, `local` |
+| Files | `ls`, `cat`, `cp`, `mv`, `rm`, `mkdir`, `touch`, `find`, `stat`, `basename`, `dirname` |
+| Text | `grep`, `sed`, `awk`, `sort`, `uniq`, `wc`, `head`, `tail`, `cut`, `tr`, `tee`, `xargs` |
+| System | `date`, `sleep`, `clear`, `jobs` |
 
 ## Usage
 
 ```
-bash-windows            # Interactive mode
-bash-windows -c 'echo hello'
-bash-windows script.sh
+bash                  # interactive shell
+bash -c 'echo hello'  # run a command string
+bash script.sh        # run a script file
+bash script.sh arg1   # pass arguments ($1, $2, ...)
 ```
 
 ### Examples
 
-```
-bash$ echo "Hello from bash-for-windows!"
-bash$ ls -la
-bash$ cd /tmp && pwd
-bash$ cat file.txt | grep pattern | wc -l
-bash$ name="Luffy" && echo $name
-bash$ mkdir -p project/src && touch project/src/main.go
+```bash
+# Variables and arithmetic
+name="World"
+echo "Hello $name"
+echo $((40 + 2))
+
+# Loops and functions
+is_even() {
+    if [ $(($1 % 2)) -eq 0 ]; then return 0; else return 1; fi
+}
+for n in 1 2 3 4 5 6; do
+    if is_even $n; then echo "$n is even"; fi
+done
+
+# Pipelines and redirection
+cat /etc/hosts | grep localhost | wc -l
+find . -name "*.go" | xargs grep -l "TODO" > todo_files.txt
+echo "result=$(date)" >> log.txt
 ```
 
-## Building
+## Build from source
 
 Requires Go 1.21+.
 
 ```bash
-# Linux
-./build.sh
-
-# Manual
-go build -o build/bash-windows .
-
-# Windows cross-compile
-GOOS=windows GOARCH=amd64 CGO_ENABLED=0 go build -o build/bash-windows.exe .
+./build.sh              # builds Linux debug + Windows .exe into build/
+./build.sh --release    # also creates release/ folder ready to distribute
 ```
 
-## Project Structure
+```bash
+# Manual cross-compile
+GOOS=windows GOARCH=amd64 CGO_ENABLED=0 go build -ldflags="-s -w" -o bash.exe .
+```
+
+## Project layout
 
 ```
-cmd/bash/        - Shell entry point
-internal/shell/  - Shell engine (parser, executor, builtins, coreutils)
-build/           - Compiled binaries
+cmd/bash/            entry point, readline REPL
+internal/shell/
+  shell.go           Execute, parseBlocks, splitStatements, IsIncomplete
+  expand.go          expandWord, tokenize, arithmetic, glob
+  exec.go            pipelines, redirections, external commands
+  control.go         if/for/while/until, function define/call
+  builtins.go        all built-in commands and coreutils
+install.ps1          Windows installer (PATH + Windows Terminal profile)
+install.bat          double-click wrapper for install.ps1
+build.sh             build script
 ```
 
 ## License