4.7.1 Combining statements

The THEN keyword separates statements that are to be performed sequentially. For example, a simple ping-pong communication can be expressed as follows:

ALL TASKS RESET ALL COUNTERS THEN
TASK 0 SENDS A 0 BYTE MESSAGE TO TASK 1 THEN
TASK 1 SENDS A 0 BYTE MESSAGE TO TASK 0 THEN
TASK 0 LOGS elapsed_usecs/2 AS "One-way latency"

There is no implicit intertask synchronization across THEN statements. Consequently, the two communications specified in the following statement will be performed concurrently:

TASK 0 ASYNCHRONOUSLY SENDS AN 8 KILOBYTE MESSAGE TO TASK 1 THEN
TASK 1 ASYNCHRONOUSLY SENDS AN 8 KILOBYTE MESSAGE TO TASK 0 THEN
ALL TASKS AWAIT COMPLETION