saga::filesystem::file Class Reference

The SAGA file package file API. More...

#include <file.hpp>

Inheritance diagram for saga::filesystem::file:

[legend]

List of all members.

Public Member Functions
	file (session const &s, saga::url url, int mode=Read)
	Creates the object.
	file (saga::url url, int mode=Read)
	Creates the object.
	file (saga::object const &o)
	Creates the object.
	file (void)
	Creates the object.
	~file (void)
	Destroys the object.
file &	operator= (saga::object const &o)
	Brief description starts here.
saga::off_t	get_size (void)
	Returns the number of bytes in the file.
saga::ssize_t	read (saga::mutable_buffer buffer, saga::ssize_t length=0)
	Reads up to length bytes from the file into the buffer.
saga::ssize_t	write (saga::const_buffer buffer, saga::ssize_t length=0)
	Writes up to length bytes from buffer into the file at the current file position.
saga::off_t	seek (saga::off_t offset, seek_mode mode)
	Reposition the file pointer.
void	read_v (std::vector< saga::filesystem::iovec > buffer_vec)
	Gather/scatter read.
void	write_v (std::vector< saga::filesystem::const_iovec > buffer_vec)
	Gather/scatter write.
saga::ssize_t	size_p (std::string pattern)
	Determine the storage size required for a pattern I/O operation.
saga::ssize_t	read_p (std::string pattern, saga::mutable_buffer buffer)
	Pattern-based read.
saga::ssize_t	write_p (std::string pattern, saga::const_buffer buffer)
	Pattern-based write.
std::vector< std::string >	modes_e ()
	List the extended modes available in this implementation, and/or on server side.
saga::size_t	size_e (std::string ext_mode, std::string specification)
	determine the storage size required for an extended I/O operation
saga::ssize_t	read_e (std::string ext_mode, std::string specification, saga::mutable_buffer buffer)
	Extended read.
saga::ssize_t	write_e (std::string ext_mode, std::string specification, saga::const_buffer buffer)
	Extended write.
Static Public Member Functions
static file	create (session const &s, saga::url url, int mode=Read)
	Factory function resembling file(session, url, int) constructor.
static file	create (saga::url url, int mode=Read)
	Factory function resembling file(url, int) constructor.
template<typename Tag>
static saga::task	create (saga::url url, int mode=Read)
	Factory function resembling entry(url, int) constructor.

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Detailed Description

The SAGA file package file API.

This class represents an open file descriptor for read/write operations on a physical file. Its concept is similar to the file descriptor returned by the open (2) call in POSIX.

Example:

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Constructor & Destructor Documentation

saga::filesystem::file::file	(	session const &	s,
		saga::url	url,
		int	mode = Read
	)

Creates the object.

saga::filesystem::file::file	(	saga::url	url,
		int	mode = Read
	)			[explicit]

Creates the object.

saga::filesystem::file::file

(

saga::object const &

o

)

[explicit]

Creates the object.

References saga::BadParameter, saga::object::File, and saga::object::get_type().

saga::filesystem::file::file

(

void

)

Creates the object.

saga::filesystem::file::~file

(

void

)

Destroys the object.

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Member Function Documentation

static file saga::filesystem::file::create	(	session const &	s,
		saga::url	url,
		int	mode = Read
	)			[inline, static]

Factory function resembling file(session, url, int) constructor.

Reimplemented from saga::name_space::entry.

static file saga::filesystem::file::create	(	saga::url	url,
		int	mode = Read
	)			[inline, static]

Factory function resembling file(url, int) constructor.

Reimplemented from saga::name_space::entry.

template<typename Tag>

static saga::task saga::filesystem::file::create	(	saga::url	url,
		int	mode = Read
	)			[inline, static]

Factory function resembling entry(url, int) constructor.

Reimplemented from saga::name_space::entry.

file & saga::filesystem::file::operator=

(

saga::object const &

o

)

Brief description starts here.

Reimplemented from saga::name_space::entry.

References saga::name_space::entry::operator=().

saga::off_t saga::filesystem::file::get_size

(

void

)

[inline]

Returns the number of bytes in the file.

saga::ssize_t saga::filesystem::file::read	(	saga::mutable_buffer	buffer,
		saga::ssize_t	length = 0
	)			[inline]

Reads up to length bytes from the file into the buffer.

Parameters:

	length	Number of bytes to be read
	buffer	Buffer to read into

Returns:

Number of bytes successfully read

saga::ssize_t saga::filesystem::file::write	(	saga::const_buffer	buffer,
		saga::ssize_t	length = 0
	)			[inline]

Writes up to length bytes from buffer into the file at the current file position.

Parameters:

	length	Number of bytes to write
	buffer	Data to write

Returns:

Number of bytes successfully written

saga::off_t saga::filesystem::file::seek	(	saga::off_t	offset,
		seek_mode	mode
	)			[inline]

Reposition the file pointer.

Parameters:

	offset	Offset in bytes to move pointer
	mode	Offset is relative to mode

Returns:

position of pointer after seek

void saga::filesystem::file::read_v

(

std::vector< saga::filesystem::iovec >

buffer_vec

)

[inline]

Gather/scatter read.

Parameters:

buffer_vec

Array of buffer_vec structs defining start (offset) and length (length) of each individual read, buffer to read into, and integer to store result into.

void saga::filesystem::file::write_v

(

std::vector< saga::filesystem::const_iovec >

buffer_vec

)

[inline]

Gather/scatter write.

Parameters:

buffer_vec

Array of buffer_vec structs defining start (offset) and length (length) of each individual write, and buffers containing the data to write

saga::ssize_t saga::filesystem::file::size_p

(

std::string

pattern

)

[inline]

Determine the storage size required for a pattern I/O operation.

Parameters:

pattern

Pattern to determine size for

Returns:

Size required for I/O operation with that pattern

saga::ssize_t saga::filesystem::file::read_p	(	std::string	pattern,
		saga::mutable_buffer	buffer
	)			[inline]

Pattern-based read.

Parameters:

	pattern	Pattern specification for read operation
	buffer	Buffer to store read bytes into

Returns:

Number of successfully read bytes

saga::ssize_t saga::filesystem::file::write_p	(	std::string	pattern,
		saga::const_buffer	buffer
	)			[inline]

Pattern-based write.

Parameters:

	pattern	Pattern specification for read operation
	buffer	Buffer to store read bytes into

Returns:

number of bytes successfully written

std::vector<std::string> saga::filesystem::file::modes_e

(

)

[inline]

List the extended modes available in this implementation, and/or on server side.

Parameters:

ret

Pattern to determine size for

Returns:

Size required for I/O operation with that pattern

saga::size_t saga::filesystem::file::size_e	(	std::string	ext_mode,
		std::string	specification
	)			[inline]

determine the storage size required for an extended I/O operation

saga::ssize_t saga::filesystem::file::read_e	(	std::string	ext_mode,
		std::string	specification,
		saga::mutable_buffer	buffer
	)			[inline]

Extended read.

Parameters:

	ext_mode	Extended mode to use
	specification	Specification of read operation
	buffer	Buffer to store read bytes into

Returns:

Number of successfully read bytes

saga::ssize_t saga::filesystem::file::write_e	(	std::string	ext_mode,
		std::string	specification,
		saga::const_buffer	buffer
	)			[inline]

Extended write.

Parameters:

	ext_mode	Extended mode to use
	specification	Specification of write operation
	buffer	Buffer to store read bytes into

Returns:

Number of successfully read bytes

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

• packages/file/file.hpp
• file.cpp