Channel

---

 #include <cio/channel.h> 

Data Structures
struct	cio_channel_op
	Description of a multiplexed channel operation. More...
struct	cio_channel
	Opaque channel object. More...
Enumerations
enum	cio_channel_op_type { CIO_CHANNEL_READ, CIO_CHANNEL_WRITE }
Functions
struct cio_channel *	cio_channel_create (size_t item_size)
struct cio_channel *	cio_channel_ref (struct cio_channel *)
void	cio_channel_unref (struct cio_channel *)
void	cio_channel_close (struct cio_channel *)
int	cio_channel_read (struct cio_channel *, void *item, size_t item_size)
int	cio_channel_write (struct cio_channel *, const void *item, size_t item_size)
int	cio_channel_select (const struct cio_channel_op *ops, int nops, int *selection)

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Enumeration Type Documentation

enum cio_channel_op_type

Enumerator:

CIO_CHANNEL_READ	Indicates a read operation.
CIO_CHANNEL_WRITE	Indicates a write operation.

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Function Documentation

void cio_channel_close

(

struct cio_channel *

c

)

Mark the channel as closed. Writing is not possible immediately after this, and reading is not possible after all pending writes have been completed. This function may be called multiple times for a single channel.

struct cio_channel* cio_channel_create

(

size_t

item_size

)

[read]

Create a new channel with a reference count of 1.

Parameters:

item_size

size of items passed through this channel (may be 0)

Returns:

a channel or NULL on error

int cio_channel_read	(	struct cio_channel *	c,
		void *	item,
		size_t	item_size
	)

Read an item from the channel.

Parameters:

	c
	item	buffer for the item or NULL if item_size is 0
	item_size	must match the channel's item size

Return values:

	1	on success
	0	if the channel is closed
	-1	on error with errno set

struct cio_channel* cio_channel_ref

(

struct cio_channel *

c

)

[read]

Increase the reference count.

Parameters:

c

Returns:

c

int cio_channel_select	(	const struct cio_channel_op *	ops,
		int	nops,
		int *	selection
	)

Perform one of multiple read and/or write operations.

Parameters:

	ops	vector of operations
	nops	number of operations
[out]	selection	storage for the index of the selected operation (set also on error; -1 on general error)

Return values:

	1	if the selected operation performed
	0	if the selected channel is closed
	-1	on error with errno set

void cio_channel_unref

(

struct cio_channel *

c

)

Decrease the reference count. The channel will be destroyed when there are no more references.

int cio_channel_write	(	struct cio_channel *	c,
		const void *	item,
		size_t	item_size
	)

Write an item to the channel.

Parameters:

	c
	item	the item or NULL if item_size is 0
	item_size	must match the channel's item size

Return values:

	1	on success
	0	if the channel is closed
	-1	on error with errno set