将int转换为void * data并获取长度（以字节为单位）

Question

I am trying to use the SDLNet_TCP_Send(TCPsocket sock, void *data, int len) function (part of the SDL_net library) and I am having a hard time figuring out how I could use this to send an int . Would I be able to do that or should I use another approach?

Answer 1

"how I could use this to send an int ... Would I be able to do that or should I use another approach?"

The function can be used to do so. You just use an address and sizeof() :

int dataToSend = 42;
SDLNet_TCP_Send(sock, &dataToSend, sizeof(dataToSend)); 

---

Depending on the data protocol you might need to obey that integer data should be sent in network byte order (to have it machine architecture independend):

#include <arpa/inet.h>

int dataToSend = htonl(42);
              // ^^^^^ Make integer network byte ordered (big endian)
SDLNet_TCP_Send(sock, &dataToSend, sizeof(dataToSend)); 

Answer 2

Given int x; you should be able to trivially call the function like this:

SDLNet_TCP_Send(socket, &x, sizeof(x));