econio_readme.md

Econio library for C and C++

Colored output and raw keyboard handling for Linux and Windows console in C and C++.

This package is created for educational purposes. For the Windows version, it uses code from the econio library written by Eric Tetz.

Screen and cursor positioning

See the functions in econio.h:

#include <stdio.h>
#include "econio.h"

int main() {
    econio_clrscr();
    econio_gotoxy(10, 0);
    printf("Hello world!\n");
    return 0;
}

Colored output

See the constants in econio.h:

econio_textcolor(COL_LIGHTGREEN);
econio_textbackground(COL_BLUE);
printf("Hello world!\n");

Buffered output

Stdout is usually buffered, and buffer is flushed when printing a newline '\n' char. So a entire scene can be drawn without flickering, then you can use econio_flush(). But econio tries to handle that the same way the standard library does, by flushing the output when input is requested.

Line-oriented input

Just use scanf() or fgets() as usual.

Raw keyboard input

Switch to raw mode using econio_rawmode(). Then use econio_kbhit() to check if a key is pressed. econio_getch() returns an ASCII code or a key code (see econio.h). Finally, call econio_normalmode().

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

int min(int a, int b) { return a < b ? a : b; }
int max(int a, int b) { return a > b ? a : b; }

int main() {
    econio_clrscr();
    printf("Use cursor keys to control the asterisk");

    int x = 40;
    int y = 12;
    econio_rawmode();
    while (true) {
        econio_gotoxy(x, y);
        econio_textcolor(COL_LIGHTGREEN);
        printf("*");
        econio_gotoxy(80, 24);
        
        int key = econio_getch();
        econio_gotoxy(x, y);
        econio_textcolor(COL_BLUE);
        printf(".");

        if (key == KEY_UP)
            y = max(y-1, 1);
        else if (key == KEY_DOWN)
            y = min(y+1, 23);
        else if (key == KEY_LEFT)
            x = max(x-1, 0);
        else if (key == KEY_RIGHT)
            x = min(x+1, 79);
        else if (key == KEY_ESCAPE)
            break;
    }
    econio_normalmode();
    
    return 0;
}

C++

Works with C++ as well. You can rename econio.c to econio.cpp, and compile as C++, if needed.

License

MIT licensed.