Ensure Ctrl+C exit prints and flushes marker

Author: brandonkachen

cli/src/hooks/use-exit-handler.ts

@@ -2,6 +2,7 @@ import { useCallback, useEffect, useRef, useState } from 'react'
 
 import { getCurrentChatId } from '../project-files'
 import { flushAnalytics } from '../utils/analytics'
+import { scheduleGracefulExit } from '../utils/graceful-exit'
 
 import type { InputValue } from '../state/chat-store'
 
@@ -66,18 +67,7 @@ export const useExitHandler = ({
       exitFallbackTimeoutRef.current = null
     }
 
-    try {
-      process.stdout.write('\nGoodbye! Exiting...\n')
-      // Ensure a clear exit marker is rendered for terminal snapshots
-      process.stdout.write('exit\n')
-    } catch {
-      // Ignore stdout write errors during shutdown
-    }
-
-    // Give the terminal a moment to render the exit message before terminating
-    setTimeout(() => {
-      process.exit(0)
-    }, 25)
+    scheduleGracefulExit()
   }, [])
 
   const flushAnalyticsWithTimeout = useCallback(async (timeoutMs = 1000) => {

cli/src/utils/graceful-exit.ts

@@ -0,0 +1,55 @@
+const EXIT_MESSAGE = '\nGoodbye! Exiting...\nexit\n'
+
+let exitStarted = false
+
+function sleep(ms: number): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, ms))
+}
+
+async function flushExitMessage(message: string): Promise<void> {
+  await new Promise<void>((resolve) => {
+    const handleDrain = () => resolve()
+    const flushed = process.stdout.write(message, handleDrain)
+    if (!flushed) {
+      process.stdout.once('drain', handleDrain)
+    }
+
+    // Always resolve eventually in case stdout is interrupted
+    setTimeout(resolve, 80)
+  })
+}
+
+/**
+ * Ensure we print a visible exit marker and give stdout a chance to flush
+ * before forcing the process to exit.
+ */
+export async function gracefulExit(options?: {
+  message?: string
+  code?: number
+}): Promise<void> {
+  if (exitStarted) return
+  exitStarted = true
+
+  const message = options?.message ?? EXIT_MESSAGE
+  const code = options?.code ?? 0
+
+  try {
+    await flushExitMessage(message)
+    // Small delay to let terminal emulators render the exit marker
+    await sleep(30)
+  } catch {
+    // Ignore errors and fall through to exit
+  }
+
+  process.exit(code)
+}
+
+/**
+ * Fire-and-forget exit helper that still flushes stdout before exiting.
+ */
+export function scheduleGracefulExit(options?: {
+  message?: string
+  code?: number
+}): void {
+  void gracefulExit(options)
+}