ACE_WIN32_Asynch_Read_File Class Reference

This class is a factory for starting off asynchronous reads on a file. More...

#include <WIN32_Asynch_IO.h>

Inheritance diagram for ACE_WIN32_Asynch_Read_File:

[legend]Collaboration diagram for ACE_WIN32_Asynch_Read_File:

[legend]List of all members.

Public Member Functions
	ACE_WIN32_Asynch_Read_File (ACE_WIN32_Proactor *win32_proactor)
	Constructor.
int	read (ACE_Message_Block &message_block, size_t bytes_to_read, u_long offset, u_long offset_high, const void *act, int priority, int signal_number=0)
int	readv (ACE_Message_Block &message_block, size_t bytes_to_read, u_long offset, u_long offset_high, const void *act, int priority, int signal_number=0)
virtual	~ACE_WIN32_Asynch_Read_File (void)
	Destructor.
int	open (const ACE_Handler::Proxy_Ptr &handler_proxy, ACE_HANDLE handle, const void *completion_key, ACE_Proactor *proactor)
int	cancel (void)
ACE_Proactor *	proactor (void) const
	Return the underlying proactor.
Private Member Functions
int	read (ACE_Message_Block &message_block, size_t bytes_to_read, const void *act, int priority, int signal_number=0)
int	readv (ACE_Message_Block &message_block, size_t bytes_to_read, const void *act, int priority, int signal_number=0)

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Detailed Description

This class is a factory for starting off asynchronous reads on a file.

Once <open> is called, multiple asynchronous <read>s can started using this class. A ACE_Asynch_Read_File::Result will be passed back to the <handler> when the asynchronous reads completes through the <ACE_Handler::handle_read_file> callback.

This class differs slightly from ACE_Asynch_Read_Stream as it allows the user to specify an offset for the read.

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Constructor & Destructor Documentation

ACE_WIN32_Asynch_Read_File::ACE_WIN32_Asynch_Read_File

(

ACE_WIN32_Proactor *

win32_proactor

)

Constructor.

ACE_WIN32_Asynch_Read_File::~ACE_WIN32_Asynch_Read_File

(

void

)

[virtual]

Destructor.

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Member Function Documentation

int ACE_WIN32_Asynch_Read_File::cancel

(

void

)

[virtual]

This cancels all pending accepts operations that were issued by the calling thread. The function does not cancel asynchronous operations issued by other threads.

Reimplemented from ACE_WIN32_Asynch_Read_Stream.

int ACE_WIN32_Asynch_Read_File::open	(	const ACE_Handler::Proxy_Ptr &	handler_proxy,
		ACE_HANDLE	handle,
		const void *	completion_key,
		ACE_Proactor *	proactor
	)			[virtual]

Initializes the factory with information which will be used with each asynchronous call. If (<handle> == ACE_INVALID_HANDLE), <ACE_Handler::handle> will be called on the <handler> to get the correct handle.

Reimplemented from ACE_WIN32_Asynch_Read_Stream.

ACE_Proactor * ACE_WIN32_Asynch_Read_File::proactor

(

void

)

const [virtual]

Return the underlying proactor.

Reimplemented from ACE_WIN32_Asynch_Read_Stream.

int ACE_WIN32_Asynch_Read_File::read	(	ACE_Message_Block &	message_block,
		size_t	bytes_to_read,
		const void *	act,
		int	priority,
		int	signal_number = 0
	)			[private, virtual]

This method belongs to ACE_WIN32_Asynch_Read_Stream. It is here to avoid the compiler warnings. We forward this call to the ACE_WIN32_Asynch_Read_Stream class.

Implements ACE_Asynch_Read_File_Impl.

int ACE_WIN32_Asynch_Read_File::read	(	ACE_Message_Block &	message_block,
		size_t	bytes_to_read,
		u_long	offset,
		u_long	offset_high,
		const void *	act,
		int	priority,
		int	signal_number = 0
	)			[virtual]

This starts off an asynchronous read. Upto <bytes_to_read> will be read and stored in the <message_block>. The read will start at <offset> from the beginning of the file.

Implements ACE_Asynch_Read_File_Impl.

int ACE_WIN32_Asynch_Read_File::readv	(	ACE_Message_Block &	message_block,
		size_t	bytes_to_read,
		const void *	act,
		int	priority,
		int	signal_number = 0
	)			[private, virtual]

Same as above but with scatter support, through chaining of composite message blocks using the continuation field.

Implements ACE_Asynch_Read_File_Impl.

int ACE_WIN32_Asynch_Read_File::readv	(	ACE_Message_Block &	message_block,
		size_t	bytes_to_read,
		u_long	offset,
		u_long	offset_high,
		const void *	act,
		int	priority,
		int	signal_number = 0
	)			[virtual]

Same as above but with scatter support, through chaining of composite message blocks using the continuation field.

Note:

Each data block payload must be at least the size of a system memory page and must be aligned on a system memory page size boundary

Implements ACE_Asynch_Read_File_Impl.

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

• WIN32_Asynch_IO.h
• WIN32_Asynch_IO.cpp

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