How can I determine whether a process is 32 or 64 bit?

Question

Given a Windows process handle, how can I determine, using C++ code, whether the process is 32 bit or 64 bit?

Answer 1

If you have handle to the module then you can do this:

IMAGE_NT_HEADERS * headers = ImageNtHeader(handle);

if ( headers->FileHeader.Machine == IMAGE_FILE_MACHINE_I386 )
{
    //module is x86
}
else if  ( headers->FileHeader.Machine == IMAGE_FILE_MACHINE_AMD64 )
{
    //module is x64
}

I took help from my own answer.