Complete port usage in Windows

Recently, I used UDP in Windows to receive data. I checked Baidu and said it was easy to use the port. I started to think it was complicated to use the port in windows, it is easier to find and use it,

After the port is used, initialize and create a thread in the main function:

G_hcompletionport = createiocompletionport (invalid_handle_value, null, 0, 0 );
Createthread (null, 0, (lpthread_start_routine) workthread,
Null, 0, null );

You need to define a structure for receiving data:

Typedef struct _ per_handle_data
{
Socket S;
Sockaddr_in ADDR;
Char Buf [buffer_size];
Int noperationtype;
} Per_handle_data;

Then assign a per_handle_data and use createiocompletionport to add the received socket handle to the completion port:

Per_handle_data * pperhandle = (per_handle_data *) malloc (sizeof (per_handle_data ));

Pperhandle-> S = socket (af_inet, sock_dgram, 0 );
Memset (& pperhandle-> ADDR, 0, sizeof (struct sockaddr_in ));
Pperhandle-> ADDR. sin_family = af_inet;
Pperhandle-> ADDR. sin_port = 8888; // UDP port number
Pperhandle-> noperationtype = 1;

BIND (pperhandle-> S, (struct sockaddr *) & pperhandle-> ADDR, sizeof (struct sockaddr ));

Createiocompletionport (handle) pperhandle-> S, g_hcompletionport, (ulong_ptr) pperhandle, 0 );

When an overlapped is allocated, wsarecv is used to receive data.

Overlapped * Pol = (overlapped *) malloc (sizeof (overlapped ));
Wsabuf Buf;
Buf. Buf = pperhandle-> Buf;
Buf. Len = buffer_size;
DWORD dwrecv;
DWORD dwflags = 0;

Ret =: wsarecv (pperhandle-> S, & Buf, 1, & dwrecv, & dwflags, Pol, null );
If (Ret <0)
Errcode = wsagetlasterror ();

While (1)

{

 

}

Use getqueuedcompletionstatus in the thread function to obtain and process the port status.

Void * workthread (void * name)
{
DWORD dwtrans;
Overlapped * poverlapped;
Per_handle_data * pperhandle;
// Overlappedplus * lpplus;
While (1)
{
Bool Bok = getqueuedcompletionstatus (g_hcompletionport, & dwtrans, (pulong_ptr) & pperhandle, & poverlapped, 0 );
If (! Bok)
{
Sleep (1 );
Continue;
}
If (pperhandle-> noperationtype = 1) // only processes the received data. pperhandle-> Buf is the content of the received data, and dwtrans is the length of the received data.
{

Processrecv (pperhandle-> Buf, dwtrans );
Wsabuf Buf;
Buf. Buf = pperhandle-> Buf;
Buf. Len = buffer_size; // parameter 2
Pperhandle-> noperationtype = 1;
DWORD nflags = 0; // parameter 4
: Wsarecv (pperhandle-> S, & Buf, 1, & dwtrans, & nflags, poverlapped, null); // continue to use wsarecv to receive data

Sleep (1 );
}

}

This is a simple program that uses the port to Implement UDP data reception.