sem.h File Reference

Semaphore management syscalls. More...

#include <ppu-lv2.h>

Go to the source code of this file.

Data Structures
struct	sys_sem_attr
	Semaphore sttributes data structure. More...

Macros
#define	SYS_SEM_ATTR_PROTOCOL   0x0002
	Default protocol for semaphore attributes.
#define	SYS_SEM_ATTR_PSHARED   0x0200
	Default sharing policy for semaphore attributes.

Typedefs
typedef struct sys_sem_attr	sys_sem_attr_t
	Semaphore sttributes data structure.

Functions
LV2_SYSCALL	sysSemCreate (sys_sem_t *sem, const sys_sem_attr_t *attr, s32 initial_val, s32 max_val)
	Create a semaphore. More...
LV2_SYSCALL	sysSemDestroy (sys_sem_t sem)
	Destroy a semaphore. More...
LV2_SYSCALL	sysSemWait (sys_sem_t sem, u64 timeout_usec)
	Wait and reserve a semaphore. More...
LV2_SYSCALL	sysSemTryWait (sys_sem_t sem)
	Reserve a semaphore (non-blocking). More...
LV2_SYSCALL	sysSemPost (sys_sem_t sem, s32 count)
	Release a semaphore. More...
LV2_SYSCALL	sysSemGetValue (sys_sem_t sem, s32 *count)
	Get the value of a semaphore. More...

Detailed Description

Semaphore management syscalls.

Function Documentation

sysSemCreate()

LV2_SYSCALL sysSemCreate	(	sys_sem_t *	sem,
		const sys_sem_attr_t *	attr,
		s32	initial_val,
		s32	max_val
	)

Create a semaphore.

Parameters

sem	Pointer to storage to the semaphore id.
attr	Pointer to the semaphore attributes.
initial_val	Initial value.
max_val	Maximum value.

Returns

zero if no error occured, nonzero otherwise.

sysSemDestroy()

LV2_SYSCALL sysSemDestroy

(

sys_sem_t

sem

)

Destroy a semaphore.

Parameters

sem	The semaphore id.

Returns

zero if no error occured, nonzero otherwise.

sysSemGetValue()

LV2_SYSCALL sysSemGetValue	(	sys_sem_t	sem,
		s32 *	count
	)

Get the value of a semaphore.

Parameters

sem	The semaphore id.
count	Pointer to storage for the semaphore value.

Returns

zero if no error occured, nonzero otherwise.

sysSemPost()

LV2_SYSCALL sysSemPost	(	sys_sem_t	sem,
		s32	count
	)

Release a semaphore.

Parameters

sem	The semaphore id.
count	Increment value.

Returns

zero if no error occured, nonzero otherwise.

sysSemTryWait()

LV2_SYSCALL sysSemTryWait

(

sys_sem_t

sem

)

Reserve a semaphore (non-blocking).

Parameters

sem	The semaphore id.

Returns

zero if the semaphore was successfully reserved, nonzero in case of error or if the semaphore value is below 1.

sysSemWait()

LV2_SYSCALL sysSemWait	(	sys_sem_t	sem,
		u64	timeout_usec
	)

Wait and reserve a semaphore.

Parameters

sem	The semaphore id.
timeout_usec	Timeout value in microseconds, or 0 if no timeout is used.

Returns

zero if the semaphore was successfully reserved, nonzero in case of error or if a timeout occured.