Here is the logic to determine which `config.json` file will be used:
1. from command line option: `--config myConfig.json`
2. `$HOME/.xds/config.json` file
-3. `<xds-server executable dir>/config.json` file
+3. `<current dir>/config.json` file
+4. `<xds-server executable dir>/config.json` file
Supported fields in configuration file are:
```json