Inheritance diagram for ACE_Asynch_Read_Dgram_Impl:
Public Member Functions
|virtual ssize_t||recv (ACE_Message_Block *message_block, size_t &number_of_bytes_recvd, int flags, int protocol_family, const void *act, int priority, int signal_number)=0|
Protected Member Functions
|Do-nothing constructor. |
|virtual ssize_t ACE_Asynch_Read_Dgram_Impl::recv||(||ACE_Message_Block *||message_block,|
|const void *||act,|
This starts off an asynchronous read. Upto <message_block->total_size()> 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. Return code of 1 means immediate success and <number_of_bytes_recvd> will contain number of bytes read. The <ACE_Handler::handle_read_dgram> method will still be called. Return code of 0 means the IO will complete proactively. Return code of -1 means there was an error, use errno to get the error code.
Scatter/gather is supported on WIN32 by using the <message_block->cont()> method. Up to ACE_IOV_MAX <message_block>'s are supported. Upto <message_block->size()> bytes will be read into each <message block>=""> for a total of <message_block->total_size()> bytes. All <message_block>'s <wr_ptr>'s will be updated to reflect the added bytes for each <message_block>
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.