nn::socket::RecvFrom Function

s32 RecvFrom(
     s32 s,
     void * buf,
     s32 len,
     s32 flags,
     SockAddrIn * sockFrom
);

	Name	Description
in	s	Specifies a socket descriptor. Specifies a socket descriptor created using the Socket or Accept function.
in	buf	Specifies a pointer to the buffer used to read out received data.
in	len	Specifies the size in bytes of the buffer used to read out received data.
in	flags	Specifies the message transmission type.
out	sockFrom	Specifies a pointer to the socket address structure used to get the communication target's address information. The len field of the socket address must be initialized appropriately (for example, to sizeof(SockAddrIn)).

Value	Description
0	For stream sockets (SOCK_STREAM), this indicates that the socket cannot accept any more messages because the remote host has finished sending messages. For datagram sockets (SOCK_DGRAM), this function does not return 0.
1	A return value of one or more indicates the number of bytes of received messages.
ENETRESET	Socket library is not initialized.
EBADF	Invalid socket descriptor.
EAGAIN	There is no data or out-of-band data waiting to be received, even when O_NONBLOCK is set in the socket descriptor (or when the MSG_DONTWAIT flag is set).
EINVAL	Invalid processing.
EOPNOTSUPP	Process not supported.
ENOTCONN	Not connected.
ECONNRESET	The connection was reset.
EINTR	Suspended.
ETIMEDOUT	Timeout.
ENETDOWN	The local network interface is down.

Attempts to receive data (messages) from a remote host via a socket.

This function usually blocks until the socket receives a message. However, if the Fcntl function has set the socket to non-blocking mode and flags is set to MSG_DONTWAIT, this function does not block and only gets the data already received at the time this function is called. For datagram sockets (SOCK_DGRAM), the entire message is read out in a single operation. If the message cannot fit into the allocated buffer and flags is not set to MSG_PEEK, any data that does not fit into the buffer is discarded. For stream sockets (SOCK_STREAM), message boundaries are ignored. In this case, data is returned to the user as it becomes usable.

2010/06/14

Initial version.