´ worker´ : invoked process handles incoming connections (default) ´ daemon´ : spawns a master process and exits. `error-log` must be configured when using this mode, as all the errors are logged to the file instead of being emitted to STDERR ´ master´ : invoked process becomes a master process (using the `share/h2o/start_server` command) and spawns a worker process for handling incoming connections. Users may send SIGHUP to the master process to reconfigure or upgrade the server. ´ test´ : tests the configuration and exits