Receive bytes from a datagram socket (IPv4)
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WSupported on Windows
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USupported on Unix
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VSupported on OpenVMS
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NSupported in Synergy .NET
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status = %SS_RECVFROM(socket, buf, bytes_received, [in_port, in_addr][, SS_MSG_PEEK])
Return value
status
Returns SS_SUCCESS (0) or one of the errors in Error codes returned by %SS_RECVFROM below. (n)
Arguments
socket
A descriptor of an open socket created by %SS_SOCKET. (i4)
buf
Buffer returned with the incoming data. (a)
bytes_received
Returned with the number of bytes received and placed into buf. (i4)
in_port
(optional) Returned with the internet port of the sending socket. (i4)
in_addr
(optional) Returned with the IPv4 address of the sending socket. (i4)
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If either in_port or in_addr is passed, they must both be passed. |
SS_MSG_PEEK
(optional) Peek into the data that is next in line to be received without removing it from the system’s buffers. (n)
Discussion
%SS_RECVFROM reads incoming data from a bound datagram socket where there has not been a previous call to %SS_CONNECT. (%SS_CONNECT establishes a permanent peer address.) It optionally returns the source port and IP address.
%SS_RECVFROM extracts data from the first queued datagram up to the size of buf. If the datagram is larger than buf, the overflow data is lost, and the error SS_EMSGSIZE is returned. If no incoming data is available at the socket, %SS_RECVFROM blocks until data arrives.
If you call this function on a connected stream socket, it functions identically to %SS_RECV.
Error codes returned by %SS_RECVFROM
See the Socket Errors table for additional information about these errors.
SS_EBADF
SS_ECONNABORTED
SS_ECONNRESET
SS_EINTR
SS_EMSGSIZE
SS_ENETDOWN
SS_ENOBUFS
SS_ENOTCONN
SS_ENOTSOCK
SS_EUNKNOWN
SS_NOTINITIALISED
