Metrologic Optimus R, Руководство по программированию

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Chapter 3 Terminal Specific Function Library 161
0: shuts down receive data path
1: shuts down send data path and send FIN (final)
2: shuts down both receive and send data path
Example
SOCKET s;
...................
if (shutdown (s, 2) < 0) {
printf ("shutdown fails on socket: %d", s);
...................
}
Description This routine shuts down part of a previously established TCP connection. Even
if both receive and send data path are shut down, closesocket() must be called
to actually close the socket.
Return
If successful, it returns 0.
On error, it returns -1.
The global variable errno is set to indicate the error condition encountered.
See Also closesocket
socket
Purpose To create a socket that is bound to a specific service provider.
Syntax SOCKET socket (int domain, int type, int protocol);
domain Protocol family; this should always be PF_INET or AF_INET.
type Socket type
protocol Depending on the
type
parameter specified, the protocol to be
used can be TCP, UDP, or ICMP.
Example SOCKET s;
s = socket (PF_INET, SOCK_STREAM, TCP);
if (s < 0) {
printf ("SOCKET allocation fails");
...................
}
Description This routine creates an endpoint for communication and returns a descriptor.
The domain argument specifies a communications domain within which
communication will take place; this selects the protocol family which
should be used.
The socket has the indicated type , which specifies the semantics of
communication.