fix(opencode): prevent process.exit() from killing parent terminal on Windows

packages/opencode/src/cli/cmd/tui.ts

@@ -14,6 +14,7 @@ import { writeHeapSnapshot } from "v8"
 import { ServerAuth } from "@/server/auth"
 import { validateSession } from "../tui/validate-session"
 import { win32InstallCtrlCGuard } from "@opencode-ai/tui/terminal-win32"
+import { safeExit } from "@/util/exit"
 
 declare global {
   const OPENCODE_WORKER_PATH: string
@@ -303,7 +304,7 @@ export const TuiThreadCommand = cmd({
         unguard?.()
       } catch {}
     }
-    process.exit()
+    safeExit()
   },
 })
 // scratch

packages/opencode/src/index.ts

@@ -27,6 +27,7 @@ import { PrCommand } from "./cli/cmd/pr"
 import { SessionCommand } from "./cli/cmd/session"
 import { DbCommand } from "./cli/cmd/db"
 import { errorMessage } from "./util/error"
+import { safeExit } from "./util/exit"
 import { PluginCommand } from "./cli/cmd/plug"
 import { Heap } from "./cli/heap"
 
@@ -137,6 +138,6 @@ try {
   // Some subprocesses don't react properly to SIGTERM and similar signals.
   // Most notably, some docker-container-based MCP servers don't handle such signals unless
   // run using `docker run --init`.
-  // Explicitly exit to avoid any hanging subprocesses.
-  process.exit()
+  // Explicitly exit (on non-Windows) to avoid any hanging subprocesses.
+  safeExit()
 }

packages/opencode/src/util/exit.ts

@@ -0,0 +1,14 @@
+export function safeExit(code: number = Number(process.exitCode ?? 0)): void {
+  if (process.platform !== "win32") {
+    process.exit(code)
+    return
+  }
+
+  // On Windows process.exit() calls ExitProcess(), which broadcasts
+  // CTRL_CLOSE_EVENT to the whole console process group. The parent shell
+  // (pwsh/cmd) is attached to the same console, so it is killed together with
+  // opencode when it exits from a TUI session (https://github.com/anomalyco/opencode/issues/28673).
+  // Setting the exit code and returning lets the process end naturally, which
+  // only detaches opencode from the console and leaves the shell alive.
+  process.exitCode = code
+}