# process.stdout

## Function

Read the status object of the started child process's stdout pipe.

## Syntax

```bt
process(program).child().stdout()
```

## Parameters

No parameters.

## Return value

| Type | Description |
| ------ | ------ |
| Object | Returns the stdout pipe status object. |
| Empty | The child process has not been started, or the child process does not have a stdout pipe. |

## Status object fields

| Field | Type | Description |
| ------ | ------ | ------ |
| kind | String | Fixed to `stdout`. |
| available | Int | The number of bytes currently buffered and not yet taken out by stdout_read. |
| closed | Bool | stdout Whether the pipe has been closed. |
| overflow | Bool | Whether the unread buffer has exceeded BT_PROCESS_PIPE_LIMIT or pipe_limit(bytes). |
| total_read | Int | The cumulative number of bytes read by the background reading thread from stdout. |
| limit | Int | The upper limit of the current stdout pipe's unread buffer. |
| read_chunk | Int | Single read chunk size. |
| timeout_ms | Int | Script reading wait timeout. |

## Example

```bt
if BT.OS == 'windows' {
    cmd = process('cmd').args(['/C', 'echo BT']).child()
} else {
    cmd = process('sh').args(['-c', 'printf BT']).child()
}

cmd.wait()
info = cmd.stdout()
result = info.kind

// Output: stdout
print result
```

## Notes

- stdout() only returns the pipeline status and does not consume buffered data.
- child() opens stdout/stderr pipes by default; child processes started by inherit_stdio() or null_stdio() have no readable stdout pipes.
- The default BT_PROCESS_PIPE_LIMIT is 1048576 bytes, BT_PROCESS_PIPE_READ_CHUNK is 8192 bytes, and BT_PROCESS_PIPE_TIMEOUT_MS is 100 milliseconds; a single Process can use pipe_limit(bytes) to override the unread buffer limit.