#include <Asynch_IO_Impl.h>
Inheritance diagram for ACE_Asynch_Read_Dgram_Impl:
Public Member Functions | |
virtual | ~ACE_Asynch_Read_Dgram_Impl (void) |
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 | |
ACE_Asynch_Read_Dgram_Impl (void) | |
Do-nothing constructor. |
ACE_Asynch_Read_Dgram_Impl::~ACE_Asynch_Read_Dgram_Impl | ( | void | ) | [virtual] |
ACE_Asynch_Read_Dgram_Impl::ACE_Asynch_Read_Dgram_Impl | ( | void | ) | [protected] |
Do-nothing constructor.
virtual ssize_t ACE_Asynch_Read_Dgram_Impl::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 | |||
) | [pure virtual] |
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.
Implemented in ACE_POSIX_Asynch_Read_Dgram, and ACE_WIN32_Asynch_Read_Dgram.