Semaphores

Functions
err_t	sys_sem_new (sys_sem_t *sem, u8_t count)
void	sys_sem_signal (sys_sem_t *sem)
u32_t	sys_arch_sem_wait (sys_sem_t *sem, u32_t timeout)
void	sys_sem_free (sys_sem_t *sem)
int	sys_sem_valid (sys_sem_t *sem)
void	sys_sem_set_invalid (sys_sem_t *sem)

Detailed Description

Function Documentation

sys_arch_sem_wait()

u32_t sys_arch_sem_wait	(	sys_sem_t *	sem,
		u32_t	timeout
	)

Wait for a semaphore for the specified timeout

Parameters

sem	the semaphore to wait for
timeout	timeout in milliseconds to wait (0 = wait forever)

Returns

time (in milliseconds) waited for the semaphore or SYS_ARCH_TIMEOUT on timeout

sys_sem_free()

void sys_sem_free

(

sys_sem_t *

sem

)

Delete a semaphore

Parameters

sem	semaphore to delete

sys_sem_new()

err_t sys_sem_new	(	sys_sem_t *	sem,
		u8_t	count
	)

Create a new semaphore

Parameters

sem	pointer to the semaphore to create
count	initial count of the semaphore

Returns

ERR_OK if successful, another err_t otherwise

sys_sem_set_invalid()

void sys_sem_set_invalid

(

sys_sem_t *

sem

)

Set a semaphore invalid so that sys_sem_valid returns 0

sys_sem_signal()

void sys_sem_signal

(

sys_sem_t *

sem

)

Signals a semaphore

Parameters

sem	the semaphore to signal

sys_sem_valid()

int sys_sem_valid

(

sys_sem_t *

sem

)

Check if a semaphore is valid/allocated: return 1 for valid, 0 for invalid