Swap devices interface

Data Structures
struct	sa_swap

Functions
int	sa_open_swap (void) SA_EXPORT
int	sa_close_swap (void) SA_EXPORT
int	sa_count_swaps (uint16_t *number) SA_EXPORT SA_NONNULL
int	sa_reset_swaps () SA_EXPORT
int	sa_get_swap (uint16_t index, struct sa_swap *dst) SA_EXPORT SA_NONNULL
int	sa_get_swaps (struct sa_swap *dst, uint16_t dst_size, uint16_t *written) SA_EXPORT SA_NONNULL

Detailed Description

Function Documentation

int sa_open_swap

(

void

)

Prepares the resources needed for retrieving swap statistics. This function exists (and is needed) only when SA_OPEN_SWAP is defined.

Returns

If successful 0 is returned, otherwise an error code is returned. If the operating system is not supported the return value will be ENOTSUP.

See also

sa_close_swap()

int sa_close_swap

(

void

)

This function closes the resources used for retrieving swap statistics. You should call it even when there was a previous error in another function of this API. This function exists (and is needed) only when SA_CLOSE_SWAP is defined.

Returns

If successful 0 is returned, otherwise an error code is returned.

See also

sa_open_swap()

int sa_count_swaps

(

uint16_t *

number

)

Gives the total number of swap file systems. You don't need to call sa_reset_swaps() before this function.

Parameters

number

The number will be stored here

Returns

If successful 0 is returned, otherwise an error code is returned.

int sa_reset_swaps

(

)

Refreshes the underlying operating system cache.

Returns

If successful 0 is returned, otherwise an error code is returned.

int sa_get_swap	(	uint16_t	index,
		struct sa_swap *	dst
	)

Retrieves statistics from a given swap index. sa_reset_swaps() should be called at least once before this function and everytime you need fresh values.

Parameters

index	The swap index. It starts from 0.
dst	Where the statistics will be stored.

Returns

If successful 0 is returned, otherwise an error code is returned. ENODEV is returned when the requested swap index was out of range.

int sa_get_swaps	(	struct sa_swap *	dst,
		uint16_t	dst_size,
		uint16_t *	written
	)

Retrieves statistics from as many swap fs as possible. sa_reset_swaps() should be called at least once before this function and everytime you need fresh values.

Parameters

dst	A buffer where the statistics will be stored.
dst_size	The number of swap fs that fits in the dst buffer. If it's not big enough dst will be filled but ENOMEM will be returned.
written	The amount of swap fs statistics written.

Returns

If successful 0 is returned, otherwise an error code is returned.