ACE_Asynch_Read_Stream Class Reference

This class is a factory for starting off asynchronous reads on a stream. This class forwards all methods to its implementation class. More...

#include <Asynch_IO.h>

Inheritance diagram for ACE_Asynch_Read_Stream:

[legend]Collaboration diagram for ACE_Asynch_Read_Stream:

[legend]List of all members.

Public Member Functions
	ACE_Asynch_Read_Stream (void)
	A do nothing constructor.
virtual	~ACE_Asynch_Read_Stream (void)
	Destructor.
int	open (ACE_Handler &handler, ACE_HANDLE handle=ACE_INVALID_HANDLE, const void *completion_key=0, ACE_Proactor *proactor=0)
int	read (ACE_Message_Block &message_block, size_t num_bytes_to_read, const void *act=0, int priority=0, int signal_number=ACE_SIGRTMIN)
virtual ACE_Asynch_Operation_Impl *	implementation (void) const
	Return the underlying implementation class.
Protected Attributes
ACE_Asynch_Read_Stream_Impl *	implementation_
	Implementation class that all methods will be forwarded to.

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Detailed Description

This class is a factory for starting off asynchronous reads on a stream. This class forwards all methods to its implementation class.

Once {open} is called, multiple asynchronous {read}s can started using this class. An ACE_Asynch_Read_Stream::Result will be passed back to the {handler} when the asynchronous reads completes through the {ACE_Handler::handle_read_stream} callback.

Definition at line 292 of file Asynch_IO.h.

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Constructor & Destructor Documentation

ACE_Asynch_Read_Stream::ACE_Asynch_Read_Stream (  void   )

A do nothing constructor. Definition at line 144 of file Asynch_IO.cpp. : implementation_ (0) { }

ACE_Asynch_Read_Stream::~ACE_Asynch_Read_Stream (  void   )  [virtual]

Destructor. Definition at line 149 of file Asynch_IO.cpp. { // Delete the implementation. delete this->implementation_; this->implementation_ = 0; }

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Member Function Documentation

ACE_Asynch_Operation_Impl * ACE_Asynch_Read_Stream::implementation (  void   )  const [virtual]

Return the underlying implementation class. Implements ACE_Asynch_Operation. Reimplemented in ACE_Asynch_Read_File. Definition at line 207 of file Asynch_IO.cpp. { return this->implementation_; }

int ACE_Asynch_Read_Stream::open (  ACE_Handler &  handler, ACE_HANDLE  handle = ACE_INVALID_HANDLE, const void *  completion_key = 0, ACE_Proactor *  proactor = 0 )

Initializes the factory with information which will be used with each asynchronous call. handler The ACE_Handler that will be called to handle completions for operations initiated using this factory. handle The handle that future read operations will use. If handle == ACE_INVALID_HANDLE, ACE_Handler::handle() will be called on @ handler to get the correct handle. Return values: 0  for success. -1  for failure; consult errno for further information. Reimplemented from ACE_Asynch_Operation. Reimplemented in ACE_Asynch_Read_File. Definition at line 157 of file Asynch_IO.cpp. References ACE_Proactor::create_asynch_read_stream(), ACE_Asynch_Operation::get_proactor(), and ACE_Asynch_Operation::open(). { // Get a proactor for/from the user. proactor = this->get_proactor (proactor, handler); // Now let us get the implementation initialized. if ((this->implementation_ = proactor->create_asynch_read_stream ()) == 0) return -1; // Call the <open> method of the base class. return ACE_Asynch_Operation::open (handler, handle, completion_key, proactor); }

int ACE_Asynch_Read_Stream::read (  ACE_Message_Block &  message_block, size_t  num_bytes_to_read, const void *  act = 0, int  priority = 0, int  signal_number = ACE_SIGRTMIN )

This starts off an asynchronous read. Upto {bytes_to_read} will be read and stored in the {message_block}. {message_block}'s {wr_ptr} will be updated to reflect the added bytes if the read operation is successful completed. Priority of the operation is specified by {priority}. On POSIX4-Unix, this is supported. Works like {nice} in Unix. Negative values are not allowed. 0 means priority of the operation same as the process priority. 1 means priority of the operation is one less than process. And so forth. On Win32, {priority} is a no-op. {signal_number} is the POSIX4 real-time signal number to be used for the operation. {signal_number} ranges from ACE_SIGRTMIN to ACE_SIGRTMAX. This argument is a no-op on non-POSIX4 systems. Definition at line 177 of file Asynch_IO.cpp. References ACE_Asynch_Read_Stream_Impl::read(). { return this->implementation_->read (message_block, bytes_to_read, act, priority, signal_number); }

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Member Data Documentation

ACE_Asynch_Read_Stream_Impl* ACE_Asynch_Read_Stream::implementation_ [protected]

Implementation class that all methods will be forwarded to. Reimplemented in ACE_Asynch_Read_File. Definition at line 359 of file Asynch_IO.h.

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

• Asynch_IO.h
• Asynch_IO.cpp

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