Re: How to simulate Window's "Press any key to continue..."

[mipri via Digitalmars-d-learn]

On Friday, 22 November 2019 at 04:22:07 UTC, FireController#1847 
wrote:
Right, but readln will only wait until the user presses the 
delimiter (by default Enter/Return). I want it to wait until 
ANY key is pressed, not a specific key

If curses is available you can use it, at the cost of completely
changing how you do I/O (in a good way if you need lots of
updates):
#! /usr/bin/env dub
/+ dub.sdl:
    dependency "nice-curses" version="~>0.2.5"
+/
import std.stdio;
import nice.curses: Curses;

void main() {
    auto curses = new Curses;
    auto scr = curses.stdscr;

    curses.setCursor(0);
    scr.addstr("Press any key to continue...");
    scr.refresh;
    curses.update;
    scr.getch;
}

If you really just briefly want getch-style input in a normal
terminal program, and still have a posix system, you can do that
with tcsetattr.

https://stackoverflow.com/questions/7469139/what-is-the-equivalent-to-getch-getche-in-linux

struct Terminal {
    import core.stdc.stdio: getchar;
    import core.sys.posix.termios:
        tcgetattr, tcsetattr, termios,
        ECHO, ICANON, TCSANOW, TCSAFLUSH;
    private termios last;

    int getch() { return getchar(); }

    int getch_once() {
        raw;
        auto r = getchar;
        reset;
        return r;
    }

    void raw() {
        termios term;
        tcgetattr(0, &last);
        term = last;
        term.c_lflag &= ~(ICANON | ECHO);
        tcsetattr(0, TCSANOW, &term);
    }

    void reset() { tcsetattr(0, TCSAFLUSH, &last); }

    ~this() { reset(); }
}

void main() {
    import std.stdio: write, writeln;
    Terminal term;

    write("Press any key to continue:");
    term.getch_once();
    writeln;
}