why terminal resize changes size of windows?

[Pavel Stehule]

Hi

I found an interesting issue. When I resize the terminal, so some windows are partially out of screen, the window size is reduced. From this moment, the window lost original size, and the size of window is related to size of screen.

It can be easy demonstrated by example:

#include <ncurses.h>

int
main()
{
    int     c;
    WINDOW *win;

    initscr();

    clear();
    noecho();
    cbreak();
    curs_set(0);
    keypad(stdscr, TRUE);

    win = newwin(20, 40, 15,15);

    timeout(250);

    while (c != 'q')
    {
        int lines, cols;

        clear();

        /* termina size */
        mvprintw(10, 10, "terminal: %d, %d", LINES, COLS);
        clrtoeol();

        /* stdscr size */
        getmaxyx(stdscr, lines, cols);
        mvprintw(11, 10, "stdscr: %d, %d", lines, cols);
        clrtoeol();

        /* win size */
        getmaxyx(win, lines, cols);
        mvprintw(12, 10, "win: %d, %d", lines, cols);
        clrtoeol();

        refresh();

        wclear(win);
        box(win, 0,0);
        wrefresh(win);

        c = getch();
    }

    endwin();
}

when running, try to reduce terminal size to 20 lines, 40 cols. After increasing terminal size, the size of window win is increased too.

What is the reason for this behaviour?

Regards

Pavel Stehule

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