ncurses newwin() and mvwin() not acting as expected - c++

Question

I am using ncurses to develop an application in C++ but both the newwin() and mvwin() functions are not working as expected. Whenever I give either of these function argument values in an attempt to make a new window that is of different size then the initial terminal window, nothing appears to happen. For example, the following code should create a new window with a height of 50, a width of 10, at location (10,10). None of this appears to be happening:
#include <ncurses.h>
#include <iostream>
using namespace std;
int main(){
initscr();
WINDOW * win = newwin(50,10,10,10);
wrefresh(win);
getch();
endwin();
return 0;
}
From the documentation I have read, it appears that a window will be created with default sizing and location if any of the arguments passed to it are invalid values, but to my knowledge all of these are valid values. Does newwin() not work like I think it does? Thank you in advance

Answer 1

The question asks about mvwin, but that does not create windows, nor is there an example in the question of a problematic call.
For newwin, zero parameters are handled specially, not "invalid values". The question shows an apparently valid call (and in a quick check, it runs as expected).
However, OP is likely confused that there is no output. That is because the program creates a window, which is empty and then reads from the standard screen.
This altered program produces output by drawing a box on the new window and then reading from that window (preventing the wrefresh associated with getch from painting over the new window):
#include <ncurses.h>
#include <iostream>
using namespace std;
int main(){
initscr();
WINDOW * win = newwin(50,10,10,10);
box(win,0,0);
wrefresh(win);
wgetch(win);
endwin();
return 0;
}

Answer 2

It sounds like there's some misunderstanding here of what ncurses does.
You mention an "attempt to make a new window that is of different size then the initial terminal window" -- if you mean a terminal emulator running in a windowing system like X/OSX/Windows, that is not what ncurses does. A "window" in ncurses is a rectangle within an existing terminal that can be updated/refreshed independently.
This might be why the comments on the other answer seem to be talking past each other.