ReadProcessMemory always reads 0 - c++

Question

I'm creating a cheat for educational purpose (on windows for now) on a small game. My error is so far is that ReadProcessMemory always reads 0.
LPCVOID addr = (LPCVOID *) 0x1228A93C; // TO-DO: c++ casts
int dest = 0;
SIZE_T read = 0;
bool error = ReadProcessMemory(process, addr, &dest, sizeof(int), &read);
if (!error) {
printf("I read %llu w/ %u at %p\r\n", read, dest, addr);
} else {
printf("This isn't working: %p / %llu\r\n", addr, read);
std::cerr << "err: " << std::to_string(::GetLastError()) << std::endl;
return (1);
}
There, I try to read the amount on money in the game. By using Cheat Engine, I get the value that changes everytime you use your money which is 0x1228A93C in the code snippet above. If I change the value pointed by this address in cheat engine, the money also change in game so I guess this is right address.
Nonetheless when I run this snippet, I get this output:
I read 0 w/ 0 at 0x1228a93c
which means it doesn't read.
Note: There is more code, in my program, above this one but this is basically finding the game window, create a snapshot of the game and find the exe module.

Answer 1

This is probably what you want:
LPCVOID addr = (LPCVOID *) 0x1228A93C; // TO-DO: c++ casts
int dest = 0;
SIZE_T read = 0;
if (ReadProcessMemory(process, addr, &dest, sizeof(int), &read))
{
printf("I read %llu w/ %u at %p\r\n", read, dest, addr);
} else {
auto lasterror = ::GetLastError(); // first thing to do: call GetLastError
printf("This isn't working: %p / %llu\r\n", addr, read);
std::cerr << "err: " << lasterror << std::endl; // std::to_string is useless here
}
In case of error the first thing to do is call GetLastError() because you don't know if cout will call SetLastError() or not.