====== Semaphore ======

An item used to arbitrate access to shared resources.

==== Description ====

Semaphores are used to protect shared resources. Before accessing a shared resource, a task must first try to lock the associated semaphore. Only one task at a time can have the semaphore locked at any one moment. This prevents multiple tasks from accessing the same data at the same time.

==== Folio ====

kernel

==== Item Type ====

SEMA4NODE

==== Create ====

''%%CreateSemaphore%%''(), [[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr022#xref15505|CreateItem]]()

==== Delete ====

[[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr036#xref16912|''%%DeleteSemaphore%%'']](), [[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr032#xref18938|DeleteItem]]()

==== Query ====

[[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr058#xref28338|''%%FindSemaphore%%'']]()

==== Use ====

[[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr098#xref18240|''%%LockSemaphore%%'']](), [[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr130#xref20743|UnlockSemaphore]](), [[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr097#xref32838|LockItem]](), [[:documentation:development:opera:pf25:ppgfldr:pgsfldr:spr:01spr129#xref25491|UnlockItem]]()