How to autofill windows user password?

[LeoMingo99]

I'm new to programming and seeking for help, thanks!

    system("runas /user:username myprogram.exe");
    //------read user password file-----// 

It won't work because when program proceeds to the system command process, it will stop to get to the reading process until user him/herself has finished the password, and that's not what I want.

So is it possible to read user password file and then automatically fill it into where users are expected to fill in by themselves?

Any reply would be appreciated!:)

[helios]

You'll need to use system APIs.
https://msdn.microsoft.com/en-us/library/windows/desktop/ms682431(v=vs.85).aspx