ACE_Asynch_Write_File Class Reference

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

#include <Asynch_IO.h>

Inheritance diagram for ACE_Asynch_Write_File:

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Collaboration diagram for ACE_Asynch_Write_File:

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List of all members.

Public Member Functions

 ACE_Asynch_Write_File (void)
 A do nothing constructor.
virtual ~ACE_Asynch_Write_File (void)
 Destructor.
int open (ACE_Handler &handler, ACE_HANDLE handle=ACE_INVALID_HANDLE, const void *completion_key=0, ACE_Proactor *proactor=0)
int write (ACE_Message_Block &message_block, size_t bytes_to_write, u_long offset=0, u_long offset_high=0, const void *act=0, int priority=0, int signal_number=ACE_SIGRTMIN)
int writev (ACE_Message_Block &message_block, size_t bytes_to_write, u_long offset=0, u_long offset_high=0, const void *act=0, int priority=0, int signal_number=ACE_SIGRTMIN)
virtual ACE_Asynch_Operation_Implimplementation (void) const
 Return the underlying implementation class.

Protected Attributes

ACE_Asynch_Write_File_Implimplementation_
 Implementation object.

Classes

class  Result
 This is that class which will be passed back to the <handler> when the asynchronous write completes. This class forwards all the methods to the implementation class. More...

Detailed Description

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

Once <open> is called, multiple asynchronous <write>s can be started using this class. A ACE_Asynch_Write_File::Result will be passed back to the <handler> when the asynchronous writes completes through the <ACE_Handler::handle_write_file> callback. This class differs slightly from ACE_Asynch_Write_Stream as it allows the user to specify an offset for the write.


Constructor & Destructor Documentation

ACE_Asynch_Write_File::ACE_Asynch_Write_File void   ) 
 

A do nothing constructor.

ACE_Asynch_Write_File::~ACE_Asynch_Write_File void   )  [virtual]
 

Destructor.


Member Function Documentation

ACE_Asynch_Operation_Impl * ACE_Asynch_Write_File::implementation void   )  const [virtual]
 

Return the underlying implementation class.

Reimplemented from ACE_Asynch_Write_Stream.

int ACE_Asynch_Write_File::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. If (<handle> == ACE_INVALID_HANDLE), <ACE_Handler::handle> will be called on the <handler> to get the correct handle.

Reimplemented from ACE_Asynch_Write_Stream.

int ACE_Asynch_Write_File::write ACE_Message_Block message_block,
size_t  bytes_to_write,
u_long  offset = 0,
u_long  offset_high = 0,
const void *  act = 0,
int  priority = 0,
int  signal_number = ACE_SIGRTMIN
 

This starts off an asynchronous write. Upto <bytes_to_write> will be written from the <message_block>, starting at the block's <rd_ptr>. The write will go to the file, starting <offset> bytes from the beginning of the file. 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, this 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.

int ACE_Asynch_Write_File::writev ACE_Message_Block message_block,
size_t  bytes_to_write,
u_long  offset = 0,
u_long  offset_high = 0,
const void *  act = 0,
int  priority = 0,
int  signal_number = ACE_SIGRTMIN
 

Same as above but with gather support, through chaining of composite message blocks using the continuation field. NOTE: In win32 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


Member Data Documentation

ACE_Asynch_Write_File_Impl* ACE_Asynch_Write_File::implementation_ [protected]
 

Implementation object.

Reimplemented from ACE_Asynch_Write_Stream.


The documentation for this class was generated from the following files:
Generated on Wed Nov 23 15:48:00 2005 for ACE by  doxygen 1.4.5