$ret = petra();
The Petra current. If there is a connection
timeout, a 0 is returned but no error is generated.
If the flag FLAG_USE_PETRA_CURRENT is found to
be 0, Online doesn't not contact the server but returns 0.
$ret = petra_is_sync_run();
Returns 1, if PETRA is in the state "Betrieb->Experimente".
$ret = petra_state();
The PETRA state, e.g.: “Betrieb->Experimente”. If there is a connection
timeout, an empty string is returned but no error is generated.
$ret = petra_wait_for_sync_run();
Returns 1, if PETRA is in the state "Betrieb->Experimente".
If not, Online waits for PETRA to enter this state. The
wait procedure may be interrupted by "STOP" (-tki) or
by pressing the space bar. In this case the function
returns 0.
If the wait state ends with "Betrieb->Experimente", Online waits
for TIME_HEATUP (or 30) seconds before it returns 1.