Change Windows console size

Question

I have been trying to figure out how to resize the console window. Here is the code of a function i am using:

#include <windows.h> 
#include <stdio.h>

#define WIDTH 70
#define HEIGHT 35

HANDLE wHnd; 

void setup() {
    SMALL_RECT windowSize = {0, 0, WIDTH - 1, HEIGHT - 1};
    COORD bufferSize = { WIDTH , HEIGHT };
    wHnd = GetStdHandle(STD_OUTPUT_HANDLE);

    SetConsoleTitle("Conway's Game of Life");
    SetConsoleWindowInfo(wHnd, 1, &windowSize); 
    SetConsoleScreenBufferSize(wHnd, bufferSize);
}

While it works for small widths and heights (like 70 and 35). it does not for the size I need (almost twice as big and yes i resized the buffersize accordingly, always a bit bigger than windowSize). Then it just is the regular size. My next thought was, since it already is quite big, why not go fullscreen.

SetConsoleDisplayMode(wHnd, CONSOLE_FULLSCREEN_MODE, 0);

Before this code snippet worked without a problem but now it does not, not even on other PCs. It stopped working on older projects too weirdly enough.

Any idea how I could launch it in fullscreen? (ALT + ENTER works) Or make the console window big at launch? I had a look at ncurses but I am on Windows 10 and don't know how to use it, besides that my Prof probably doesn't want me to use external libraries. Thanks for your help! Let me know if I forgot something.

Answer 1

To maximize the console window you can do:

C++

#include <cstdlib>
#include <string>
#include <iostream>
#include <memory>
#include <type_traits>

#include <windows.h>

std::string get_last_error_msg()
{
    auto error_code{ GetLastError() };
    if (!error_code)
        return {};

    LPSTR buffer{};
    auto size{ FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
        nullptr, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), reinterpret_cast<LPSTR>(&buffer), 0, nullptr) };

    // use a unique_ptr for buffer since the ctor of string could throw
    std::unique_ptr<std::remove_pointer_t<decltype(buffer)>, decltype(&LocalFree)> p{ buffer, LocalFree };
    std::string message{ p.get(), size };
    return message;
}

bool maximize_console()
{
    auto console_window{ GetConsoleWindow() };

    if (!console_window) {
        std::cerr << "GetConsoleWindow() failed :(\n\n";
        return false;
    }

    auto console_out{ GetStdHandle(STD_OUTPUT_HANDLE) };
    if (console_out == INVALID_HANDLE_VALUE) {
        std::cerr << "GetStdHandle() failed with \"" << get_last_error_msg() << "\" :(\n\n";
        return false;
    }

    auto largest_size{ GetLargestConsoleWindowSize(console_out) };
    if (!largest_size.X && !largest_size.Y) {
        std::cerr << "GetLargestConsoleWindowSize() failed with \"" << get_last_error_msg() << "\" :(\n\n";
        return false;
    }

    --largest_size.X;
    --largest_size.Y;

    if (!SetConsoleScreenBufferSize(console_out, largest_size)) {
        std::cerr << "SetConsoleScreenBufferSize() failed with \"" << get_last_error_msg() << "\" :(\n\n";
        return false;
    }

    if (!ShowWindow(console_window, SW_MAXIMIZE)) {
        std::cerr << "ShowWindow() failed :(\n\n";
        return false;
    }

    return true;
}

int main()
{
    if (!maximize_console())
        return EXIT_FAILURE;
}

---

C

#include <stdbool.h>
#include <stdio.h>

#include <windows.h>

LPSTR get_last_error_msg(void)
{
    DWORD error_code = GetLastError();
    if (!error_code)
        return LocalAlloc(LMEM_ZEROINIT, 1);

    LPSTR buffer = NULL;
    FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&buffer, 0, NULL);

    return buffer;
}

bool maximize_console(void)
{
    HWND console_window = GetConsoleWindow();

    if (!console_window) {
        fputs("GetConsoleWindow() failed :(\n", stderr);
        return false;
    }

    HANDLE console_out = GetStdHandle(STD_OUTPUT_HANDLE);
    if (console_out == INVALID_HANDLE_VALUE) {
        LPSTR buffer = get_last_error_msg();
        fprintf(stderr, "GetStdHandle() failed with \"%s\" :(\n\n", buffer);
        LocalFree(buffer);
        return false;
    }

    COORD largest_size = GetLargestConsoleWindowSize(console_out);
    if (!largest_size.X && !largest_size.Y) {
        LPSTR buffer = get_last_error_msg();
        fprintf(stderr, "GetLargestConsoleWindowSize() failed with \"%s\" :(\n\n", buffer);
        LocalFree(buffer);
        return false;
    }

    --largest_size.X;
    --largest_size.Y;

    if (!SetConsoleScreenBufferSize(console_out, largest_size)) {
        LPSTR buffer = get_last_error_msg();
        fprintf(stderr, "SetConsoleScreenBufferSize() failed with \"%s\" :(\n\n", buffer);
        LocalFree(buffer);
    }

    if (!ShowWindow(console_window, SW_MAXIMIZE)) {
        fputs("ShowWindow() failed :(\n", stderr);
        return false;
    }

    return true;
}

int main(void)
{
    if (!maximize_console())
        return EXIT_FAILURE;
}