updates

kernel/bin/help

@@ -5,6 +5,6 @@ function bareStdin(ctx) {
 
 async function run(ctx, argv) {
   ctx.console.log(
-    'Bare OS — builtins: cd, export, exit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
+    'Bare OS — builtins: cd, export, exit, quit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
   )
 }

kernel/init.js

@@ -7,7 +7,7 @@ async function start(ctx) {
   const rel = await drive.get('/etc/os-release')
   if (rel) console.log(b4a.toString(rel))
   console.log(
-    'Bare operating system — POSIX-ish shell: cd, export, exit | try: help, ls /bin, pwd'
+    'Bare operating system — POSIX-ish shell: cd, export, exit, quit | try: help, ls /bin, pwd'
   )
   while (true) {
     const line = await readLine('bare-os> ')

packages/bare-os-booter/lib/fish-readline.js

@@ -5,8 +5,15 @@ import {
   ghostFromHistory,
   searchHistorySubstring
 } from './fish-history.js'
+import {
+  clearEntireLine,
+  clearScreenDown,
+  clearCurrentLine,
+  cursorTo,
+  moveCursor
+} from './tty-ansi.js'
 
-export const SHELL_BUILTINS = ['cd', 'export', 'exit']
+export const SHELL_BUILTINS = ['cd', 'export', 'exit', 'quit']
 
 /** @type {Record<string, string[]>} */
 export const FLAG_COMPLETION = {
@@ -30,8 +37,54 @@ export function fuzzyMatch(str, pattern) {
   return patternIdx === pattern.length
 }
 
+/** Visible length for cursor placement (strip CSI sequences, not only SGR `m`). */
 function stripAnsi(str) {
-  return str.replace(/\x1b\[[0-9;]*m/g, '')
+  return str.replace(/\x1b\[[\d;?]*[A-Za-z]/g, '')
+}
+
+/**
+ * TTY width for soft-wrap math. If the real terminal is narrower than we assume,
+ * we treat the line as one row and only clear one physical row — the rest of the
+ * prompt (e.g. `[user@…`) stays as garbage and the user sees a lone `>`.
+ * When width is unknown (common on Bare/Pear), use a conservative default.
+ * @param {import('stream').Writable & { columns?: number }} stdout
+ */
+function effectiveTermCols(stdout) {
+  const w =
+    Number(stdout.columns) ||
+    Number(globalThis.process?.stdout?.columns) ||
+    Number(globalThis.process?.env?.COLUMNS)
+  if (Number.isFinite(w) && w > 0) {
+    return Math.max(20, Math.min(Math.trunc(w), 512))
+  }
+  return 40
+}
+
+/**
+ * Visible column/row after `str` on a terminal (soft-wrap model; ASCII width 1).
+ * @returns {{ cols: number, rows: number }}
+ */
+function displayPos(str, termCols) {
+  const col = Math.max(1, termCols)
+  let offset = 0
+  let rows = 0
+  for (let i = 0; i < str.length; i++) {
+    const c = str[i]
+    if (c === '\n') {
+      rows += Math.ceil(offset / col) || 1
+      offset = 0
+      continue
+    }
+    if (c === '\t') {
+      const tabSize = 8
+      offset += tabSize - (offset % tabSize)
+      continue
+    }
+    offset += 1
+  }
+  const cols = offset % col
+  rows += (offset - cols) / col
+  return { cols, rows }
 }
 
 /**
@@ -148,6 +201,10 @@ export async function createFishReadLine(ctx, opts) {
   let historySearchResults = []
   let historySearchIndex = -1
   let savedLine = ''
+  /** Previous cursor row (0-based) within the prompt+input block; used for wrap-aware redraw. */
+  let prevCursorRows = 0
+  /** Rows spanned by last painted prompt+input+ghost (>=1); forces full refresh when >1. */
+  let prevPaintRowCount = 0
 
   /** @type {((v: string | null) => void) | null} */
   let pendingResolve = null
@@ -161,47 +218,123 @@ export async function createFishReadLine(ctx, opts) {
   }
 
   function render(showHistorySearch = false) {
+    void showHistorySearch
+
     if (lines.length > 1) {
+      prevCursorRows = 0
+      prevPaintRowCount = 0
       for (let i = 0; i < lines.length; i++) {
-        if (typeof stdout.cursorTo === 'function') stdout.cursorTo(0)
+        clearCurrentLine(stdout)
-        if (typeof stdout.clearLine === 'function') stdout.clearLine(0)
         if (i < lines.length - 1) stdout.write('\n')
       }
-      if (typeof stdout.cursorTo === 'function') stdout.cursorTo(0)
+      clearCurrentLine(stdout)
       stdout.write('\x1b[' + (lines.length - 1) + 'A')
-    } else {
-      if (typeof stdout.clearLine === 'function') stdout.clearLine(0)
-      if (typeof stdout.cursorTo === 'function') stdout.cursorTo(0)
-    }
 
-    for (let i = 0; i < lines.length; i++) {
+      for (let i = 0; i < lines.length; i++) {
-      const isLastLine = i === lines.length - 1
+        const isLastLine = i === lines.length - 1
-      const prompt = getPrompt(i > 0)
+        const prompt = getPrompt(i > 0)
-      const currentLine = lines[i]
+        const currentLine = lines[i]
-      const coloredLine = highlightLine(currentLine, i)
+        const coloredLine = highlightLine(currentLine, i)
-      stdout.write(prompt + coloredLine)
+        stdout.write(prompt + coloredLine)
-      if (
+        if (
-        isLastLine &&
+          isLastLine &&
-        ghost &&
+          ghost &&
-        currentLine.length > 0 &&
+          currentLine.length > 0 &&
-        ghost.startsWith(currentLine) &&
+          ghost.startsWith(currentLine) &&
-        !historySearchActive
+          !historySearchActive
-      ) {
+        ) {
-        stdout.write(`\x1b[90m${ghost.slice(currentLine.length)}\x1b[0m`)
+          stdout.write(`\x1b[90m${ghost.slice(currentLine.length)}\x1b[0m`)
+        }
+        if (!isLastLine) stdout.write('\n')
       }
-      if (!isLastLine) stdout.write('\n')
+
+      const cursorRowPrompt = getPrompt(currentLineIndex > 0)
+      const visualPromptLength = stripAnsi(cursorRowPrompt).length
+      const col = visualPromptLength + cursor
+      cursorTo(stdout, col)
+      return
     }
 
     if (historySearchActive) {
+      prevCursorRows = 0
+      prevPaintRowCount = 0
+      clearEntireLine(stdout)
+      const prompt = getPrompt(false)
+      const currentLine = lines[0]
+      const coloredLine = highlightLine(currentLine, 0)
+      stdout.write(prompt + coloredLine)
+      if (
+        ghost &&
+        currentLine.length > 0 &&
+        ghost.startsWith(currentLine)
+      ) {
+        stdout.write(`\x1b[90m${ghost.slice(currentLine.length)}\x1b[0m`)
+      }
       stdout.write(
         `\n\x1b[36m(reverse-i-search)'${historySearchQuery}':\x1b[0m ${historySearchResults[historySearchIndex] || ''}`
       )
+      const vp = stripAnsi(prompt).length
+      cursorTo(stdout, vp + cursor)
+      return
     }
 
-    const lastPrompt = getPrompt(lines.length > 1)
+    const termCols = effectiveTermCols(stdout)
-    const visualPromptLength = stripAnsi(lastPrompt).length
+    const prompt = getPrompt(false)
-    if (typeof stdout.cursorTo === 'function') {
+    const currentLine = lines[0]
-      stdout.cursorTo(visualPromptLength + cursor)
+    const coloredLine = highlightLine(currentLine, 0)
+    const showGhost = Boolean(
+      ghost &&
+        currentLine.length > 0 &&
+        ghost.startsWith(currentLine)
+    )
+    const ghostWrite = showGhost
+      ? `\x1b[90m${ghost.slice(currentLine.length)}\x1b[0m`
+      : ''
+    const visPrompt = stripAnsi(prompt)
+    const ghostVis = showGhost ? ghost.slice(currentLine.length) : ''
+    const fullVis = visPrompt + currentLine + ghostVis
+    const strBefore = visPrompt + currentLine.slice(0, cursor)
+    const lineEnd = displayPos(fullVis, termCols)
+    const curEnd = displayPos(strBefore, termCols)
+    const paintRowCount = lineEnd.rows + 1
+    const needFullRefresh =
+      lineEnd.rows > 0 ||
+      curEnd.rows > 0 ||
+      prevCursorRows > 0 ||
+      prevPaintRowCount > 1
+
+    const out = prompt + coloredLine + ghostWrite
+
+    function moveUp(n) {
+      if (n <= 0) return
+      moveCursor(stdout, 0, -n)
+    }
+    function toCol0() {
+      cursorTo(stdout, 0)
+    }
+    function clrDown() {
+      clearScreenDown(stdout)
+    }
+    function toCol(x) {
+      cursorTo(stdout, x)
+    }
+
+    if (!needFullRefresh) {
+      clearEntireLine(stdout)
+      stdout.write(out)
+      toCol(curEnd.cols)
+      prevCursorRows = 0
+      prevPaintRowCount = paintRowCount
+    } else {
+      moveUp(prevCursorRows)
+      toCol0()
+      clrDown()
+      stdout.write(out)
+      toCol(curEnd.cols)
+      const diff = lineEnd.rows - curEnd.rows
+      if (diff > 0) moveUp(diff)
+      prevCursorRows = curEnd.rows
+      prevPaintRowCount = paintRowCount
     }
   }
 
@@ -296,6 +429,8 @@ export async function createFishReadLine(ctx, opts) {
     historySearchQuery = ''
     historySearchResults = []
     historySearchIndex = -1
+    prevCursorRows = 0
+    prevPaintRowCount = 0
     if (resolve) {
       if (cmd === null) resolve(null)
       else resolve(typeof cmd === 'string' ? cmd : '')
@@ -323,6 +458,8 @@ export async function createFishReadLine(ctx, opts) {
       ghost = ''
       tabMatches = []
       tabIndex = -1
+      prevCursorRows = 0
+      prevPaintRowCount = 0
       render()
       return
     }
@@ -555,6 +692,8 @@ export async function createFishReadLine(ctx, opts) {
   return function fishReadLine(_prompt) {
     return new Promise((resolve) => {
       pendingResolve = resolve
+      prevCursorRows = 0
+      prevPaintRowCount = 0
       line = ''
       lines = ['']
       currentLineIndex = 0

packages/bare-os-booter/lib/shell.js

@@ -278,7 +278,7 @@ export async function execShellLine(ctx, line) {
           const eq = a.indexOf('=')
           if (eq > 0) env[a.slice(0, eq)] = expandWord(a.slice(eq + 1), env)
         }
-      } else if (name === 'exit') {
+      } else if (name === 'exit' || name === 'quit') {
         code = 'exit'
       } else {
         const childCtx =

packages/bare-os-booter/lib/tty-ansi.js

@@ -0,0 +1,70 @@
+/**
+ * Minimal CSI helpers for TTY output (no node:readline).
+ * Semantics match Node readline: x/y are 0-based; CHA/CUP use 1-based parameters.
+ */
+
+/** @param {unknown} n */
+function clampNonNegInt(n) {
+  if (!Number.isFinite(n)) return 0
+  const i = Math.trunc(n)
+  return i < 0 ? 0 : i
+}
+
+/**
+ * @param {import('stream').Writable | null | undefined} stream
+ * @param {number} x 0-based column
+ * @param {number} [y] 0-based row; if omitted, CHA only
+ */
+export function cursorTo(stream, x, y) {
+  if (stream == null || typeof stream.write !== 'function') return
+  const cx = clampNonNegInt(x)
+  if (typeof y === 'number' && Number.isFinite(y)) {
+    const cy = clampNonNegInt(y)
+    stream.write(`\x1b[${cy + 1};${cx + 1}H`)
+  } else {
+    stream.write(`\x1b[${cx + 1}G`)
+  }
+}
+
+/**
+ * @param {import('stream').Writable | null | undefined} stream
+ * @param {number} dx
+ * @param {number} dy
+ */
+export function moveCursor(stream, dx, dy) {
+  if (stream == null || typeof stream.write !== 'function') return
+  const ddx = Number.isFinite(dx) ? Math.trunc(dx) : 0
+  const ddy = Number.isFinite(dy) ? Math.trunc(dy) : 0
+  if (ddy < 0) stream.write(`\x1b[${-ddy}A`)
+  else if (ddy > 0) stream.write(`\x1b[${ddy}B`)
+  if (ddx < 0) stream.write(`\x1b[${-ddx}D`)
+  else if (ddx > 0) stream.write(`\x1b[${ddx}C`)
+}
+
+/**
+ * Erase from cursor to end of display (ED default).
+ * @param {import('stream').Writable | null | undefined} stream
+ */
+export function clearScreenDown(stream) {
+  if (stream == null || typeof stream.write !== 'function') return
+  stream.write('\x1b[J')
+}
+
+/**
+ * Carriage return + erase entire line (EL 2K).
+ * @param {import('stream').Writable | null | undefined} stream
+ */
+export function clearEntireLine(stream) {
+  if (stream == null || typeof stream.write !== 'function') return
+  stream.write('\r\x1b[2K')
+}
+
+/**
+ * Column 0 then EL entire line (same effect as clearEntireLine on most terminals).
+ * @param {import('stream').Writable | null | undefined} stream
+ */
+export function clearCurrentLine(stream) {
+  if (stream == null || typeof stream.write !== 'function') return
+  cursorTo(stream, 0)
+  stream.write('\x1b[2K')
+}

packages/bare-os-booter/test.js

@@ -17,6 +17,13 @@ import {
   searchHistorySubstring
 } from './lib/fish-history.js'
 import { fuzzyMatch, SHELL_BUILTINS } from './lib/fish-readline.js'
+import {
+  clearCurrentLine,
+  clearEntireLine,
+  clearScreenDown,
+  cursorTo,
+  moveCursor
+} from './lib/tty-ansi.js'
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url))
 
@@ -186,6 +193,8 @@ async function run(ctx, argv) {
   t.is(ctx.vfs.getcwd(), '/bin')
   await execShellLine(ctx, 'xy one two')
   t.is(got[0], 'xy one two')
+  t.is(await execShellLine(ctx, 'exit'), 'exit')
+  t.is(await execShellLine(ctx, 'quit'), 'exit')
   await store.close()
   rmSync(dir, { recursive: true, force: true })
 })
@@ -251,3 +260,44 @@ test('fuzzyMatch and SHELL_BUILTINS', async (t) => {
   t.ok(fuzzyMatch('basename', 'bse'))
   t.ok(SHELL_BUILTINS.includes('cd'))
 })
+
+test('tty-ansi emits CSI for cursor and clear', async (t) => {
+  /** @type {string[]} */
+  const chunks = []
+  const stream = {
+    write(s) {
+      chunks.push(typeof s === 'string' ? s : String(s))
+    }
+  }
+
+  cursorTo(stream, 0)
+  t.is(chunks.join(''), '\x1b[1G')
+  chunks.length = 0
+
+  cursorTo(stream, 4)
+  t.is(chunks.join(''), '\x1b[5G')
+  chunks.length = 0
+
+  cursorTo(stream, 2, 1)
+  t.is(chunks.join(''), '\x1b[2;3H')
+  chunks.length = 0
+
+  moveCursor(stream, 0, -2)
+  t.is(chunks.join(''), '\x1b[2A')
+  chunks.length = 0
+
+  moveCursor(stream, 3, 1)
+  t.is(chunks.join(''), '\x1b[1B\x1b[3C')
+  chunks.length = 0
+
+  clearScreenDown(stream)
+  t.is(chunks.join(''), '\x1b[J')
+  chunks.length = 0
+
+  clearEntireLine(stream)
+  t.is(chunks.join(''), '\r\x1b[2K')
+  chunks.length = 0
+
+  clearCurrentLine(stream)
+  t.is(chunks.join(''), '\x1b[1G\x1b[2K')
+})

packages/bare-os-coreutils/src/help.js

@@ -1,5 +1,5 @@
 async function run(ctx, argv) {
   ctx.console.log(
-    'Bare OS — builtins: cd, export, exit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
+    'Bare OS — builtins: cd, export, exit, quit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
   )
 }

packages/bare-os-seeder/kernel/bin/help

@@ -5,6 +5,6 @@ function bareStdin(ctx) {
 
 async function run(ctx, argv) {
   ctx.console.log(
-    'Bare OS — builtins: cd, export, exit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
+    'Bare OS — builtins: cd, export, exit, quit | /bin: basename cat clear date dirname echo env false head help hostname id ls nl pathchk printenv pwd rm seq sleep sort tail test touch true tty uname wc which whoami'
   )
 }

packages/bare-os-seeder/kernel/init.js

@@ -7,7 +7,7 @@ async function start(ctx) {
   const rel = await drive.get('/etc/os-release')
   if (rel) console.log(b4a.toString(rel))
   console.log(
-    'Bare operating system — POSIX-ish shell: cd, export, exit | try: help, ls /bin, pwd'
+    'Bare operating system — POSIX-ish shell: cd, export, exit, quit | try: help, ls /bin, pwd'
   )
   while (true) {
     const line = await readLine('bare-os> ')