readLaunchPid function
Reads the app or flutter-tools PID written during launch.
Returns an empty string until one of the expected PID files exists.
Implementation
String readLaunchPid() {
for (final path in [appPidFile, pidFile]) {
final file = File(path);
if (!file.existsSync()) {
continue;
}
final pid = file.readAsStringSync().trim();
if (pid.isNotEmpty) {
return pid;
}
}
return '';
}