Question

So I try

char buffer[1000];
GetEnvironmentVariable("PATH",(char*)&buffer,sizeof(buffer));
std::cout << buffer << std::endl;

to check if it exists but I do not see how to see if its empty? And It couts some really bad output=(

Answer 1

MSDN has this to say about GetEnvironmentVariable:

If the function fails, the return value is zero. If the specified environment variable was not found in the environment block, GetLastError returns ERROR_ENVVAR_NOT_FOUND.

(Source: http://msdn.microsoft.com/en-us/library/ms683188.aspx)

So I guess you should test the function’s return value:

char buffer[1000];
if(GetEnvironmentVariable("PATH", buffer, sizeof(buffer)))
{
    // non-zero, go ahead!
    std::cout << buffer << std::endl;
}
else
{
    // zero, something went wrong
}