start_sequence

QNX SDP8.0PLMS User's GuideAPIConfigurationDeveloper

Format

start_sequence = ["pre_start", "main", "post_start"]

Description

The start_sequence keyword notifies plms to execute a start tasks from left to right. plms executes each function defined in the tasks. If any function fails, plms interprets that start sequence to have failed.

If you don't define start_sequence, only the main task is executed for the start action.

If you define start_sequence and the main task is not present in the list, plms doesn't spawn the main process and only executes the defined tasks.

Default

The default value is main.
Note:
If you don't define the main task and specify a start sequence for the component, then it's assumed that nothing is to be started and the component is deemed to have started successfully.

Multiplicity

Zero or one instance in a component block.

Constraints

  • The tasks must be resolvable at the end of the component parsing. If the sequence contains any unresolvable tasks, the configuration files are rejected.

  • The component is considered to have been started when all the tasks defined in the start_sequence are successful.

  • Execution of the start_sequence is aborted if the tasks fail.

  • A task can appear only once in the start_sequence list, and the tasks are executed as specified. If a task is used in start_sequence, then it's not allowed to be use in other task sequences.

  • Empty start_sequence list will be rejected during parsing.

  • If the main task is defined and not included in the start_sequence, then the main task isn't executed, but all tasks in the start_sequence will be executed.

  • If a stop action is requested when a component is in start state, then the start is aborted, and stop_sequence is executed.

Example

start_sequence = ["main", "post_main1"]
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