fix(coding-agent): fire session shutdown on TERM and HUP closes #3212

packages/coding-agent/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Fixed `session_shutdown` to fire on `SIGHUP` and `SIGTERM` in interactive, print, and RPC modes so extensions can run shutdown cleanup on those signal-driven exits ([#3212](https://github.com/badlogic/pi-mono/issues/3212))
 - Fixed screenshot path parsing to handle lower case am/pm in macOS screenshot filenames ([#3194](https://github.com/badlogic/pi-mono/pull/3194) by [@jay-aye-see-kay](https://github.com/jay-aye-see-kay))
 - Fixed interactive auto-retry status updates to show a live countdown during backoff instead of a static retry delay message ([#3187](https://github.com/badlogic/pi-mono/issues/3187))
 

packages/coding-agent/docs/extensions.md

@@ -283,7 +283,7 @@ user sends another prompt ◄─────────────────
 /model or Ctrl+P (model selection/cycling)
   └─► model_select
 
-exit (Ctrl+C, Ctrl+D)
+exit (Ctrl+C, Ctrl+D, SIGHUP, SIGTERM)
   └─► session_shutdown
 ```
 
@@ -403,7 +403,7 @@ pi.on("session_tree", async (event, ctx) => {
 
 #### session_shutdown
 
-Fired on exit (Ctrl+C, Ctrl+D, SIGTERM).
+Fired on exit (Ctrl+C, Ctrl+D, SIGHUP, SIGTERM).
 
 ```typescript
 pi.on("session_shutdown", async (_event, ctx) => {

packages/coding-agent/src/core/extensions/types.ts

@@ -479,7 +479,7 @@ export interface SessionCompactEvent {
 	fromExtension: boolean;
 }
 
-/** Fired on process exit */
+/** Fired on graceful process shutdown paths such as Ctrl+C, Ctrl+D, SIGHUP, and SIGTERM. */
 export interface SessionShutdownEvent {
 	type: "session_shutdown";
 }

packages/coding-agent/src/modes/interactive/interactive-mode.ts

@@ -212,6 +212,7 @@ export class InteractiveMode {
 
 	// Agent subscription unsubscribe function
 	private unsubscribe?: () => void;
+	private signalCleanupHandlers: Array<() => void> = [];
 
 	// Track if editor is in bash mode (text starts with !)
 	private isBashMode = false;
@@ -477,6 +478,8 @@ export class InteractiveMode {
 	async init(): Promise<void> {
 		if (this.isInitialized) return;
 
+		this.registerSignalHandlers();
+
 		// Load changelog (only show new entries, skip for resumed sessions)
 		this.changelogMarkdown = this.getChangelogForDisplay();
 
@@ -2905,6 +2908,7 @@ export class InteractiveMode {
 	private async shutdown(): Promise<void> {
 		if (this.isShuttingDown) return;
 		this.isShuttingDown = true;
+		this.unregisterSignalHandlers();
 		await this.runtimeHost.dispose();
 
 		// Wait for any pending renders to complete
@@ -2927,6 +2931,30 @@ export class InteractiveMode {
 		await this.shutdown();
 	}
 
+	private registerSignalHandlers(): void {
+		this.unregisterSignalHandlers();
+
+		const signals: NodeJS.Signals[] = ["SIGTERM"];
+		if (process.platform !== "win32") {
+			signals.push("SIGHUP");
+		}
+
+		for (const signal of signals) {
+			const handler = () => {
+				void this.shutdown();
+			};
+			process.on(signal, handler);
+			this.signalCleanupHandlers.push(() => process.off(signal, handler));
+		}
+	}
+
+	private unregisterSignalHandlers(): void {
+		for (const cleanup of this.signalCleanupHandlers) {
+			cleanup();
+		}
+		this.signalCleanupHandlers = [];
+	}
+
 	private handleCtrlZ(): void {
 		// Keep the event loop alive while suspended. Without this, stopping the TUI
 		// can leave Node with no ref'ed handles, causing the process to exit on fg
@@ -4785,6 +4813,7 @@ export class InteractiveMode {
 	}
 
 	stop(): void {
+		this.unregisterSignalHandlers();
 		if (this.loadingAnimation) {
 			this.loadingAnimation.stop();
 			this.loadingAnimation = undefined;

packages/coding-agent/src/modes/print-mode.ts

@@ -33,6 +33,34 @@ export async function runPrintMode(runtimeHost: AgentSessionRuntime, options: Pr
 	let exitCode = 0;
 	let session = runtimeHost.session;
 	let unsubscribe: (() => void) | undefined;
+	let disposed = false;
+	const signalCleanupHandlers: Array<() => void> = [];
+
+	const disposeRuntime = async (): Promise<void> => {
+		if (disposed) return;
+		disposed = true;
+		unsubscribe?.();
+		await runtimeHost.dispose();
+	};
+
+	const registerSignalHandlers = (): void => {
+		const signals: NodeJS.Signals[] = ["SIGTERM"];
+		if (process.platform !== "win32") {
+			signals.push("SIGHUP");
+		}
+
+		for (const signal of signals) {
+			const handler = () => {
+				void disposeRuntime().finally(() => {
+					process.exit(signal === "SIGHUP" ? 129 : 143);
+				});
+			};
+			process.on(signal, handler);
+			signalCleanupHandlers.push(() => process.off(signal, handler));
+		}
+	};
+
+	registerSignalHandlers();
 
 	const rebindSession = async (): Promise<void> => {
 		session = runtimeHost.session;
@@ -128,8 +156,10 @@ export async function runPrintMode(runtimeHost: AgentSessionRuntime, options: Pr
 		console.error(error instanceof Error ? error.message : String(error));
 		return 1;
 	} finally {
-		unsubscribe?.();
-		await runtimeHost.dispose();
+		for (const cleanup of signalCleanupHandlers) {
+			cleanup();
+		}
+		await disposeRuntime();
 		await flushRawStdout();
 	}
 }

packages/coding-agent/src/modes/rpc/rpc-mode.ts

@@ -75,6 +75,8 @@ export async function runRpcMode(runtimeHost: AgentSessionRuntime): Promise<neve
 
 	// Shutdown request flag
 	let shutdownRequested = false;
+	let shuttingDown = false;
+	const signalCleanupHandlers: Array<() => void> = [];
 
 	/** Helper for dialog methods with signal/timeout support */
 	function createDialogPromise<T>(
@@ -336,7 +338,23 @@ export async function runRpcMode(runtimeHost: AgentSessionRuntime): Promise<neve
 		});
 	};
 
+	const registerSignalHandlers = (): void => {
+		const signals: NodeJS.Signals[] = ["SIGTERM"];
+		if (process.platform !== "win32") {
+			signals.push("SIGHUP");
+		}
+
+		for (const signal of signals) {
+			const handler = () => {
+				void shutdown(signal === "SIGHUP" ? 129 : 143);
+			};
+			process.on(signal, handler);
+			signalCleanupHandlers.push(() => process.off(signal, handler));
+		}
+	};
+
 	await rebindSession();
+	registerSignalHandlers();
 
 	// Handle a single command
 	const handleCommand = async (command: RpcCommand): Promise<RpcResponse> => {
@@ -614,12 +632,19 @@ export async function runRpcMode(runtimeHost: AgentSessionRuntime): Promise<neve
 	 */
 	let detachInput = () => {};
 
-	async function shutdown(): Promise<never> {
+	async function shutdown(exitCode = 0): Promise<never> {
+		if (shuttingDown) {
+			process.exit(exitCode);
+		}
+		shuttingDown = true;
+		for (const cleanup of signalCleanupHandlers) {
+			cleanup();
+		}
 		unsubscribe?.();
 		await runtimeHost.dispose();
 		detachInput();
 		process.stdin.pause();
-		process.exit(0);
+		process.exit(exitCode);
 	}
 
 	async function checkShutdownRequested(): Promise<void> {