c - initialize winsock without wsadata using WSAStartup?

Question

Basically I wanted to know if you can initialize a winsock without creating WSADATA variable or feeding the WSADATA value directly to WSAStartup function?

I tried :

WSAStartup(0x202, NULL);
WSAStartup(0x202, (WSADATA *)0x00);

with above, the socket fails to recv() but then again it start to work if you have:

WSADATA wsaData;
WSAStartup(0x202, &wsaData);

Based on documentation, it says "It allows an application or DLL to specify the version of Windows Sockets required and retrieve details of the specific Windows Sockets implementation". So, could we not directly define a memory location to store the returned value?

question from:https://stackoverflow.com/questions/65910249/initialize-winsock-without-wsadata-using-wsastartup

Answer 1

Basically I wanted to know if you can initialize a winsock without creating WSADATA variable or feeding the WSADATA value directly to WSAStartup function?

The call to WSAStartup() is required, otherwise most Winsock functions will fail with an WSANOTINITIALISED error. And WSAStartup() itself requires a pointer to allocated memory to fill in with WSADATA data. This is not optional.

So, could we not directly define a memory location to store the returned value?

That is exactly what declaring a variable does. But more generally, yes you can certainly pass in any non-NULL memory address, as long as it is a valid memory address within the calling process, and has been allocated to hold at least sizeof(WSADATA) number of bytes.