W&T 57630, Руководство пользователя

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TCP / UDP - Binary
The Web-IO always returns 0.
The connection through which the BinInfo structure was
exchanged is automatically closed by the Web-IO.
5.6.6 BINARY - The IO structures
To enable simply communication between the application program
on the computer and the Web-IO, there is a variety of structures
(variable fields) which define the format and content of the data
which are exchanged between the application program and the
Web-IO.
IO structures are offered for the following functions:
.
Reading inputs
.
Reading inputs and outputs
.
Setting outputs
.
Reading counters
.
Resetting counters
.
Parameterizing cyclical and automatic messaging for state
changes.
The application program employs the easy-to-use socket interface
(Windows: WinSock, UNIX, Linux: Berkley Sockets) for exchanging
data with the Web-IO over the network via TCP/IP in the form of
these data structure.
The IO structures are independent of the selected network protocol
(TCP or UDP).
The choice of which protocol to use, UDP or TCP, depends on
the type of application. Both protocols have their advantages
and disadvantages that need to be weighed depending on the
application you are creating.
i
Help for socket programming including the basics of
TCP/IP can be found in a short, easy to understand guide
„Ready for TCP/IP Sockets in 1 Day“. Program examples for