On a related note -- when I see the minuscule filesize of the original Zelda game on emulators, I marvel at how little text/code/information could produce how much wonder, how far-reaching impact, and how many hours of enchantment for me.

https://en.wikipedia.org/wiki/The_Legend_of_Zelda_(video_gam...

I extracted the linux executable and was surprised to find that both readelf and objdump choke on it despite it loading and running correctly. Some investigation reveals that the name of the dynamic linker was shoved into the "unused" fields in the PT_DYNAMIC header entry to save space:

  Program Headers:
    Type           Offset             VirtAddr           PhysAddr
                   FileSiz            MemSiz              Flags  Align
    INTERP         0x0000000000000088 0x0000000000010088 0x0000000000010088
                   0x000000000000001c 0x000000000000001c         0x0
        [Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]
    DYNAMIC        0x00000000000000e0 0x00000000000100e0 0x6c2f343662696c2f  <-- "/lib64/ld-linux-x86-64.so.2"
                   0x2d78756e696c2d64 0x732e34362d363878         0x322e6f
  readelf: Error: the dynamic segment offset + size exceeds the size of the file
    LOAD           0x0000000000000000 0x0000000000010000 0x0000000000000000
                   0x0000000000001dc0 0x0000000000005660  RWE    0x1000

Two questions:

1. Was this done manually or is there a tool you're using which does this? I see other size-reduction tricks in here as well.

2. Does anybody know of a tool for examining executables which doesn't crap out on binaries like this?

For me:

- Browser: works after renaming to .html

- Linux: "./snake.com: line 20: lzma: command not found". Installing the xz package makes it work (already had XWayland enabled so X11 worked, but may be needed if you have a strict Wayland session).

- Windows: As either .com or renaming to .exe I get "The application was unable to start correctly (0xc0000005). Click OK to close the application." Not sure how to make this one work, it's definitely not AV related though (I have that stripped in this sandbox VM).

Edit: Got it working in all 3 now. On Windows I still had DEP enabled on all programs to test some apps earlier, turning that back off allowed it to launch.

    $ chmod +x snake.com
    $ ./snake.com

    Cannot open assembly './snake.com': File does not contain a valid CIL image.

    $ bash snake.com

Not cross-platform, but I'm reminded of the kkrieger game for Windows which was a 96k FPS game that looked visually impressive for the time.

https://web.archive.org/web/20100304155706/http://www.thepro...

What entertains me most is that the thing contains three independent implementations of a graphics-based game, strung together, wrapped into a crafty multiplatform loader... and it all still takes 13 kiB.

i wonder if such a mechanism could be "enhanced" to produce a true "universal" binary, using a source-to-source compiled language like Haxe?

With Haxe, you can write the application once, target both win32 and linux by compiling to C++ (which then you compile using the platform specific tooling for each paltform), and then target html by compiling to javascript. Then use the same concatenation mechanism and header abuse as described in the article to have all three targets merged into one file that can then be run on all platforms!

One of the interesting things about Polyglot is that nobody did it any sooner. It would have been feasible a decade ago or two ago.

I love the idea of applications which exist in one file which you can run anywhere. I've been working towards this with my serverless platform; you can build complex data-driven apps with just one .html file and mostly declarative HTML markup (thanks to web-components which are loaded from a remote server). With modern browser features, you don't need a bundling system. Once you do away with it; a whole universe is opened up.

The ability to load .html files over the file:// protocol is a powerful, often neglected feature. In practice, it means you can double-click an HTML file and it runs an app in your browser instantly.

Semi-related: Windows EXE files are runnable in DOS (at least when DOS was a thing, so for Windows 3.1x or 9x), but most of the time the DOS part just prints "This program requires Microsoft Windows." and exits. An exception is regedit.exe, that one can use to import registry values even in DOS. (Huh, although, how does it do that without using Windows API?)

The binary relies on the runtime, so yes it is nice.

Forma instance, a static compiled and linked "hello world" in C on Linux is around ~785KB

    $ musl-gcc -xc -static -Wl,-z,norelro -Wl,-z,nosectionheader -Wl,-z,noseparate-code -s - <<eof
    #include <stdio.h>
    int
    main(void) {
            static const char s[] = "Hello, World!\n";
            fwrite(s, (sizeof s)-1, 1, stdout);
    }
    eof
    $ ./a.out
    Hello, World!
    $ ls -l a.out
    -rwxr-xr-x 1 oguz oguz 4976 Jan 12 09:38 a.out

    $ musl-gcc -xc -static -nostdlib -fcf-protection=none -fno-asynchronous-unwind-tables -fomit-frame-pointer -Wl,-z,norelro -Wl,-z,nosectionheader -Wl,-z,noseparate-code -s - -lc <<eof
    #include <unistd.h>
    void
    _start(void) {
            static const char s[] = "Hello, World!\n";
            write(1, s, (sizeof s)-1);
            _exit(0);
    }
    eof
    $ ./a.out
    Hello, World!
    $ ls -l a.out
    -rwxr-xr-x 1 oguz oguz 487 Jan 12 09:58 a.out

Reminds me of the Cosmopolitan project: https://github.com/jart/cosmopolitan

Wonder why they don't give a demo/link to the browser version

You don't need to rename it to an html file, just serve it with with the following header:

Content-Type: text/html

Very clever!

Quite cool.

You could distribute it as `.html` only, and use JS to offer a local download link to itself in the correct extension. A polyglot installer, of sorts.

For example, this gist is an HTML that, when opened, offers a download zip of its DOM in whatever state it currently is:

https://gist.github.com/alganet/c904acb57282402fc0bd724f1eeb...

I think you can use something similar to get the entire page contents as a blob, but I never tested with binary data in actual browsers. Perhaps even patch it to avoid the initial windows error.