SysSock2Listen (FUN) ¶ FUNCTION SysSock2Listen : RTS_IEC_RESULT Listen on a TCP server socket for new connection. InOut: Scope Name Type Comment Return SysSock2Listen RTS_IEC_RESULT Runtime system error code (see CmpErrors.library). Input hSocket RTS_IEC_HANDLE Handle to the socket diMaxConnections DINT Maximum number of connections allowed

SysSock2Ntohl (FUN) ¶ FUNCTION SysSock2Ntohl : UDINT Convert a UDINT value from ethernet byte order into host format. InOut: Scope Name Type Comment Return SysSock2Ntohl UDINT Converted UDINT value Input ulNet UDINT Ethernet value

SysSock2Ntohs (FUN) ¶ FUNCTION SysSock2Ntohs : WORD Convert a WORD value from ethernet byte order into host format. InOut: Scope Name Type Comment Return SysSock2Ntohs WORD Converted WORD value Input usNet WORD Ethernet value

SysSock2Recv (FUN) ¶ FUNCTION SysSock2Recv : __XINT Receive data from a TCP socket. InOut: Scope Name Type Comment Return SysSock2Recv __XINT Number of bytes received. 0 if failed. Input hSocket RTS_IEC_HANDLE Handle to the socket pbyBuffer POINTER TO BYTE Buffer to read data from the socket diBufferSize __XINT Maximum length of the buffer diFlags DINT The flags parameter can be used to influence the behavior of the function beyond the options specified for the associated socket. The semantics of this function are determined by the socket options and the flags parameter. The latter is constructed by using the bitwise OR operator with any of the SOCKET_MSG values. See category “Message flags”. pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSock2RecvFrom (FUN) ¶ FUNCTION SysSock2RecvFrom : __XINT Receive a message from a connectionless socket (UDP). NOTE: With some IP stacks (LwIP for example, which is used with the CODESYS Control RTE), it is necessary to set the SOCKET_SO_BROADCAST socket option (SOCKET_SOL level) in order to be able to receive broadcast UDP messages with the SysSock2RecvMsg() and SysSock2RecvFrom() functions. InOut: Scope Name Type Comment Return SysSock2RecvFrom __XINT Number of bytes received Input hSocket RTS_IEC_HANDLE Handle to the socket pbyBuffer POINTER TO BYTE Buffer to read data from the socket diBufferSize __XINT Maximum length of the buffer diFlags DINT The flags parameter can be used to influence the behavior of the function beyond the options specified for the associated socket. The semantics of this function are determined by the socket options and the flags parameter. The latter is constructed by using the bitwise OR operator with any of the SOCKET_MSG values. pSockAddr POINTER TO SOCKADDRESS Socket address and port to receive data from diSockAddrSize DINT Size of socket address structure pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSock2RecvMsg (FUN) ¶ FUNCTION SysSock2RecvMsg : __XINT Receives a message from a socket. NOTE: For querying the SOCKET_MSG_BCAST message flag the IP_PKTINFO socket option has to be set on the socket. NOTE: With some IP stacks (LwIP for example, which is used with the CODESYS Control RTE), it is necessary to set the SOCKET_SO_BROADCAST socket option (SOCKET_SOL level) in order to be able to receive broadcast UDP messages with the SysSock2RecvMsg() and SysSock2RecvFrom() functions. NOTE: If no messages are available at the socket and SOCKET_FIONBIO is not set on the socket, SysSock2RecvMsg() shall block until a message arrives. InOut: Scope Name Type Comment Return SysSock2RecvMsg __XINT Upon successful completion, SysSock2RecvMsg() shall return the length of the message in bytes. If no messages are available to be received and the peer has performed an orderly shutdown, SysSock2RecvMsg() shall return 0 and set * pResult to ERR_SOCK_CLOSED. Otherwise, the function shall return 0 and set * pResult to indicate the error. Input hSocket RTS_IEC_HANDLE Handle to the socket. pMessage POINTER TO SOCK_RECVMSG_MSG Points to a SOCK_RECVMSG_MSG structure, containing both the buffer to store the source address and the buffer for the incoming message. The length and format of the address depend on the address family of the socket. The msgFlags and msgFlagsSupported members are ignored on input, but may contain meaningful values on output. flags DWORD Specifies the type of message reception. Values of this argument are formed by logically OR’ing zero or more of the SOCKET_MSG values. See category “Message flags”. pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSock2Send (FUN) ¶ FUNCTION SysSock2Send : __XINT Sent data to a TCP socket. InOut: Scope Name Type Comment Return SysSock2Send __XINT Number of sent bytes. 0 if failed. Input hSocket RTS_IEC_HANDLE Handle to the socket pbyBuffer POINTER TO BYTE Buffer with data to sent diBufferSize __XINT Maximum length of the buffer diFlags DINT The flags parameter can be used to influence the behavior of the function beyond the options specified for the associated socket. The semantics of this function are determined by the socket options and the flags parameter. The latter is constructed by using the bitwise OR operator with any of the SOCKET_MSG values. pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSock2Select (FUN) ¶ FUNCTION SysSock2Select : RTS_IEC_RESULT Check a number of sockets for activity. All sockets added to the FD_SETs have to be of the same type (Standard or TLS) InOut: Scope Name Type Comment Return SysSock2Select RTS_IEC_RESULT Runtime system error code (see CmpErrors.library): ERR_OK ERR_SOCK_TIMEDOUT, if timeout expired Input hSocket RTS_IEC_HANDLE Handle to one of the socket handles added to the FD Sets. diWidth DINT Number of sockets in the |SOCKET_FD_SET| structure, so |SOCKET_FD_SETSIZE| must be used here. pfdRead POINTER TO SOCKET_FD_SET Optional pointer to the structure |SOCKET_FD_SET| defining the socket set to be checked for reading. It is also possible to set this parameter to 0. pfdWrite POINTER TO SOCKET_FD_SET Optional pointer to the structure |SOCKET_FD_SET| defining the socket set to be checked for writing. It is also possible to set this parameter to 0. pfdExcept POINTER TO SOCKET_FD_SET Optional pointer to structure |SOCKET_FD_SET| that defines the socket set the error state has to be checked. It is also possible to set this parameter to 0. ptvTimeout POINTER TO SOCKET_TIMEVAL Pointer to maximum timespan which the function SysSockSelect waits for a response: ptvTimeout=NULL: Infinite wait ptvTimeout->tv_sec=-1, ptvTimeout->tv_usec=-1: Infinite wait ptvTimeout->tv_sec=0, ptvTimeout->tv_usec=0: No wait pdiReady POINTER TO DINT Number of sockets that are ready for IO

SysSock2SendTo (FUN) ¶ FUNCTION SysSock2SendTo : __XINT Send a message over a connectionless socket (UDP). InOut: Scope Name Type Comment Return SysSock2SendTo __XINT Number of bytes sent. Input hSocket RTS_IEC_HANDLE Handle to the socket pbyBuffer POINTER TO BYTE Buffer with send data diBufferSize __XINT Length of data to send. If diBufferSize = 0 ERR_PARAMETER is returned diFlags DINT The flags parameter can be used to influence the behavior of the function beyond the options specified for the associated socket. The semantics of this function are determined by the socket options and the flags parameter. The latter is constructed by using the bitwise OR operator with any of the SOCKET_MSG values. pSockAddr POINTER TO SOCKADDRESS Socket address and port to sent data to diSockAddrSize DINT Size of socket address structure pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSock2SetOption (FUN) ¶ FUNCTION SysSock2SetOption : RTS_IEC_RESULT Set options of a specified socket. InOut: Scope Name Type Comment Return SysSock2SetOption RTS_IEC_RESULT Runtime system error code (see CmpErrors.library). Input hSocket RTS_IEC_HANDLE Handle to the socket diLevel DINT Level of the socket diOption DINT Socket option command pdiOptionValue POINTER TO BYTE Pointer to the option value diOptionLen DINT Lenght of option value