dmlite::IOHandler Class Reference

IO interface. More...

#include <io.h>

List of all members.

Public Types
	kSet = SEEK_SET
	Beginning of the file.
	kCur = SEEK_CUR
	Current position.
	kEnd = SEEK_END
	End of file.
enum	Whence { kSet = SEEK_SET, kCur = SEEK_CUR, kEnd = SEEK_END }
Public Member Functions
virtual	~IOHandler ()
	Virtual destructor.
std::string	getImplId (void) const throw ()
	String ID of the implementation.
virtual void	close (void) throw (DmException)
	Close.
virtual int	fileno (void) throw (DmException)
	Return internal file descriptor, if any.
virtual struct::stat	fstat (void) throw (DmException)
virtual size_t	read (char *buffer, size_t count) throw (DmException)
virtual size_t	write (const char *buffer, size_t count) throw (DmException)
virtual size_t	readv (const struct iovec *vector, size_t count) throw (DmException)
virtual size_t	writev (const struct iovec *vector, size_t count) throw (DmException)
virtual size_t	pread (void *buffer, size_t count, off_t offset) throw (DmException)
virtual size_t	pwrite (const void *buffer, size_t count, off_t offset) throw (DmException)
virtual void	seek (off_t offset, Whence whence) throw (DmException)
virtual off_t	tell (void) throw (DmException)
	Return the cursor position.
virtual void	flush (void) throw (DmException)
	Flush the buffer.
virtual bool	eof (void) throw (DmException)
	Return true if end of file.

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Detailed Description

IO interface.

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Member Enumeration Documentation

enum dmlite::IOHandler::Whence

Enumerator:

kSet	Beginning of the file.
kCur	Current position.
kEnd	End of file.

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Constructor & Destructor Documentation

virtual dmlite::IOHandler::~IOHandler

(

)

[virtual]

Virtual destructor.

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Member Function Documentation

virtual void dmlite::IOHandler::close

(

void

)

throw (DmException) [virtual]

Close.

virtual bool dmlite::IOHandler::eof

(

void

)

throw (DmException) [virtual]

Return true if end of file.

virtual int dmlite::IOHandler::fileno

(

void

)

throw (DmException) [virtual]

Return internal file descriptor, if any.

virtual void dmlite::IOHandler::flush

(

void

)

throw (DmException) [virtual]

Flush the buffer.

virtual struct ::stat dmlite::IOHandler::fstat

(

void

)

throw (DmException) [virtual]

Gets information about a file descriptor.

Note:

Not all plug-ins will fill all the fields, but st_size is a reasonable expectation.

Default implementation combining seek/tell is provided.

std::string dmlite::IOHandler::getImplId

(

void

)

const throw () [inline]

String ID of the implementation.

virtual size_t dmlite::IOHandler::pread	(	void *	buffer,
		size_t	count,
		off_t	offset
	)			throw (DmException) [virtual]

Read from the given offset without changing the file offset.

Parameters:

	buffer	Where to put the data.
	count	Number of bytes to read.
	offset	The operation offset.

Note:

A default implementation using read/seek/tell is provided.

virtual size_t dmlite::IOHandler::pwrite	(	const void *	buffer,
		size_t	count,
		off_t	offset
	)			throw (DmException) [virtual]

Write from the given offset without changing the file offset.

Parameters:

	buffer	Data to write.
	count	Number of bytes to read.
	offset	The operation offset.

Note:

A default implementation using read/seek/tell is provided.

virtual size_t dmlite::IOHandler::read	(	char *	buffer,
		size_t	count
	)			throw (DmException) [virtual]

Read.

Parameters:

	buffer	Where to store the data.
	count	Number of bytes to read.

Returns:

Number of bytes actually read.

virtual size_t dmlite::IOHandler::readv	(	const struct iovec *	vector,
		size_t	count
	)			throw (DmException) [virtual]

Read into multiple buffers.

Parameters:

	vector	An array with 'count' iovec structs.
	count	Number of elements in vector.

Returns:

The total size read.

Note:

See man readv.

A default implementation using read is provided.

virtual void dmlite::IOHandler::seek	(	off_t	offset,
		Whence	whence
	)			throw (DmException) [virtual]

Move the cursor.

Parameters:

	offset	The offset.
	whence	Reference.

virtual off_t dmlite::IOHandler::tell

(

void

)

throw (DmException) [virtual]

Return the cursor position.

virtual size_t dmlite::IOHandler::write	(	const char *	buffer,
		size_t	count
	)			throw (DmException) [virtual]

Write.

Parameters:

	buffer	Data to write.
	count	Number of bytes to write.

Returns:

Number of bytes actually written.

virtual size_t dmlite::IOHandler::writev	(	const struct iovec *	vector,
		size_t	count
	)			throw (DmException) [virtual]

Write from multiple buffers.

Parameters:

	vector	An array with 'count' iovec structs.
	count	Number of elements in vector.

Returns:

The total size written.

Note:

See man writev.

A default implementation using write is provided.

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The documentation for this class was generated from the following file:

• include/dmlite/cpp/io.h

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