truein between the two time operations mode.
There are two time operation mode: normal, which represents the passing of the physical time, and the virtual where the clock goes as fast as possible (see @is_fastforward).
In the curse of a
::antescofo antescofo::startfrom... XXX command, the
program is first run in fastforward mode, using the virtual time. When
::antescofo XXX is reached in thescore, the time is
paused and the switch to the normal time is done only when an event is
detected by the listening machine.
The predicate @is_paused is always false in an antescofo program. But it can be true in a script (script can be used in the Antescofo standalone version to execute a sequence of antescofo command).