Core concepts

• A thread is a schedulable context with its own stack. Application priorities are positive; larger values are more urgent. Yield lets equal-priority peers run and does not authorize lower-priority work.

• Static storage belongs to the caller. The build generates object storage size/alignment for the configuration. Initialize the kernel and objects, then start scheduling; initialization-table objects are constructed during emb_kernel_init().

• A wait completes with one result: satisfaction, timeout, cancellation or deliberate destruction. Resource hand-off reserves the satisfied mutex/semaphore unit for the chosen waiter rather than making it race another consumer.

• A mutex has an owner and optional inheritance/ceiling/recursion. Inheritance and deadlock detection have depth limits. A semaphore has no owner and is not a substitute for a mutex protecting shared state.

• A notification is a bit set, not a counter or a message. Repeated sets coalesce. The owner waits; ISR-safe code can set application bits. Semaphore binding takes a one-bit mask; bind/check existing readiness and drain it before waiting again.

• Duration, instant and timeout are distinct types. Convert a duration with EMB_TIMEOUT() for a timeout parameter. Periodic work uses absolute deadlines; tiny’s 32-bit absolute comparisons have a half-range constraint.

• Context annotations decide whether an operation is ISR-safe. Passing EMB_NO_WAIT alone does not grant ISR permission. Blocking under a caller-held critical section or scheduler lock is misuse.

The current POINTER handle model provides type/lifecycle diagnostics in checked builds and no capability-right security. Partitions, TABLE handles and restart are future protection mechanisms. Target specifications give detailed contracts; Project status distinguishes their implemented portions.