1. Process Identification (PId)
Each SDL process has a unique identifier, a value of data type PId.
Special value NULL (no process)
Predefined variables
SELF: the process itself
OFFSPRING: the most recent process created by SELF
PARENT: SELF is OFFSPRING of PARENT
SENDER: the process that sent the last signal received and processed by SELF
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2. Use of PId Variables
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3. Use of PId Variables (II)
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4. 5.5: Dynamic Generation of Process Instances
In SDL, a process may create other processes.
The creation is shown by a dashed line from PARENT to OFFSPRING.
Blocks cannot be generated dynamically.
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5. Creation of Processes
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6. PROCESS CUControl
Create Symbol
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7. Process parameters
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8. Stop Symbol Processes are created by their parent.
A process terminates when it reaches a stop symbol. (Note: processes may not kill each other).
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