sema.c File Reference

#include "thread.h"

Data Structures
struct	Sema
Functions
void	Ns_SemaInit (Ns_Sema *semaPtr, int count)
void	Ns_SemaDestroy (Ns_Sema *semaPtr)
void	Ns_SemaWait (Ns_Sema *semaPtr)
void	Ns_SemaPost (Ns_Sema *semaPtr, int count)

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Function Documentation

void Ns_SemaDestroy

(

Ns_Sema *

semaPtr

)

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Ns_SemaDestroy --

Destroy a semaphore. This routine is almost never used as synchronization objects are normally created at process startup and exist until the process exits.

Results: None.

Side effects: None.

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void Ns_SemaInit	(	Ns_Sema *	semaPtr,
		int	count
	)

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Ns_SemaInit --

Initialize a semaphore. Note that because semaphores are initialized with a starting count they cannot be automatically created on first use as with other synchronization objects.

Results: None.

Side effects: None.

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void Ns_SemaPost	(	Ns_Sema *	semaPtr,
		int	count
	)

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Ns_SemaPost --

Increment a semaphore count, releasing waiting threads if needed.

Results: None.

Side effects: Threads waiting on the condition, if any, may be resumed.

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void Ns_SemaWait

(

Ns_Sema *

semaPtr

)

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Ns_SemaWait --

Wait for a semaphore count to be greater than zero.

Results: None.

Side effects: Calling thread may wait on the condition.

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