# FAQ

> Short answers about controlroom — flagstaff or controlroom, React, ink, modes, stdout versus stderr, testing, the mouse and CommonJS — each with where to read more.

Source: https://controlroom.interlace.tools/docs/faq

## flagstaff or controlroom?

If a program only draws (spinners, progress, task lists, boxes, tables) under what it has
already printed, it is [flagstaff](https://flagstaff.interlace.tools/docs), even when the drawing
is busy. If it reads keys while it draws, panes, tabs, focus, an input line, it is controlroom.
A question asked once, a confirm or a pick, is neither: it is a prompt, and prompts are
[caique](https://caique.interlace.tools/docs)'s. controlroom builds on flagstaff, so a pane is a
flagstaff component either way.

## Do I need React?

Only for `controlroom/ink`. The native API, `open()` and everything on the
[guides](/docs/guides/screens), never loads React; `react` and `react-reconciler` are optional
peers that only `controlroom/ink` imports.

## Is `controlroom/ink` exactly ink?

It passes 1304 of 1304 cases of ink 8.0.0's own suite, where real ink 8.0.0 passes 1303, and
102 of 102 of @inkjs/ui 2.0.0's. The cases set aside and the differences that remain are on
[Compatibility](/docs/drop-ins).

## Which screen will my program get?

A live one when roundel's policy says `tty` and stdin can go raw. Otherwise a static one: `json`
if you passed `json: true`, `accessible` if `CLI_ACCESSIBLE` is set, `ci` if `CI` is set and
stdout is not a terminal, and `pipe` for the rest. The table is on
[Getting started](/docs/getting-started#which-screen-a-program-gets).

## Where does output go?

The live screen, a pipe, CI and accessible mode write to **stdout**. Under `--json`, the events go
to **stderr**, and stdout is left for your program's own result.

## Will my program hang in CI?

No call waits for a key unless keys are being read, and keys are read only on a terminal whose
stdin can go raw. In CI, in a pipe, with `< file` or under an agent, a screen reads no keys, and
an input line reads piped stdin or ends at once
([Live and static](/docs/guides/static-projection#never-a-wait)).

## How do I test a screen?

`open()` takes a runtime instead of reading `process`, so a test passes its own: streams that
collect what is written, an environment, and a manual clock from `flagstaff/loop`. The
transcript is then a fixed string. controlroom's own `screen.test.ts` and the two recipes'
tests are written that way.

## Does it support the mouse?

No, and none is planned. Clicks, the wheel and drags are out of scope; a program that depends on
them should stay where it is ([Why controlroom](/docs/why-controlroom#what-is-left-out)).

## Can I use it from CommonJS?

The package is ESM with a `default` condition, so `require('controlroom')` loads it through
Node's `require(esm)` on the versions the package supports, Node 20.19+ and 22.13+.
`shape.test.ts` installs the packed tarball and requires it.

## What is `status`?

The reserved release's one export, kept so a program that read it still loads. It is still
`'reserved'`; the package is not.