Perlwm – a window manager written entirely in Perl | Hacker News Reader

Perlwm – a window manager written entirely in Perl

perlwm.sourceforge.net

44 pointslelf10 comments

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... and last updated in 2004.

Stable software! Rare these days.

Liked, subscribed, followed on twitter, starred on github, and added on myspace

Excelsior and Huzzah! This is a match made in heaven! Perl and X-Windows ICCCM are like two peas in a pod!

https://en.wikipedia.org/wiki/Pod_People_(Invasion_of_the_Bo...

https://medium.com/@donhopkins/the-x-windows-disaster-128d39...

>As a result, one of the most amazing pieces of literature to come out of the X Consortium is the “Inter Client Communication Conventions Manual,” more fondly known as the “ICCCM”, “Ice Cubed,” or “I39L” (short for “I, 39 letters, L”). It describes protocols that X clients must use to communicate with each other via the X server, including diverse topics like window management, selections, keyboard and colormap focus, and session management. In short, it tries to cover everything the X designers forgot and tries to fix everything they got wrong. But it was too late — by the time ICCCM was published, people were already writing window managers and toolkits, so each new version of the ICCCM was forced to bend over backwards to be backward compatible with the mistakes of the past.

>The ICCCM is unbelievably dense, it must be followed to the last letter, and it still doesn’t work. ICCCM compliance is one of the most complex ordeals of implementing X toolkits, window managers, and even simple applications. It’s so difficult, that many of the benefits just aren’t worth the hassle of compliance. And when one program doesn’t comply, it screws up other programs. This is the reason cut-and-paste never works properly with X (unless you are cutting and pasting straight ASCII text), drag-and-drop locks up the system, colormaps flash wildly and are never installed at the right time, keyboard focus lags behind the cursor, keys go to the wrong window, and deleting a popup window can quit the whole application. If you want to write an interoperable ICCCM compliant application, you have to crossbar test it with every other application, and with all possible window managers, and then plead with the vendors to fix their problems in the next release.

>In summary, ICCCM is a technological disaster: a toxic waste dump of broken protocols, backward compatibility nightmares, complex nonsolutions to obsolete nonproblems, a twisted mass of scabs and scar tissue intended to cover up the moral and intellectual depravity of the industry’s standard naked emperor.

>Using these toolkits is like trying to make a bookshelf out of mashed potatoes. - Jamie Zawinski

[...]

>The color situation is a total flying circus. The X approach to device independence is to treat everything like a MicroVAX framebuffer on acid. A truly portable X application is required to act like the persistent customer in Monty Python’s “Cheese Shop” sketch, or a grail seeker in “Monty Python and the Holy Grail.” Even the simplest applications must answer many difficult questions:

>WHAT IS YOUR DISPLAY?

    display = XOpenDisplay("unix:0");

>WHAT IS YOUR ROOT?

    root = RootWindow(display, DefaultScreen(display));

>AND WHAT IS YOUR WINDOW?

    win = XCreateSimpleWindow(display, root, 0, 0, 256, 256, 1,
                              BlackPixel(
                                  display,
                                  DefaultScreen(display)),
                              WhitePixel(
                                  display,
                                  DefaultScreen(display)));

>OH ALL RIGHT, YOU CAN GO ON.

>(the next client tries to connect to the server)

>WHAT IS YOUR DISPLAY?

    display = XOpenDisplay("unix:0");

>WHAT IS YOUR COLORMAP?

    cmap = DefaultColormap(display, DefaultScreen(display));

>AND WHAT IS YOUR FAVORITE COLOR?

    favorite_color = 0; /* Black. */
    /* Whoops! No, I mean: */
    favorite_color = BlackPixel(display, DefaultScreen(display));
    /* AAAYYYYEEEEE!! */

>(client dumps core & falls into the chasm)

>WHAT IS YOUR DISPLAY?

    display = XOpenDisplay("unix:0");

>WHAT IS YOUR VISUAL?

    struct XVisualInfo vinfo;
    if (XMatchVisualInfo(display, DefaultScreen(display),
                         8, PseudoColor, &vinfo) != 0)
        visual = vinfo.visual;

>AND WHAT IS THE NET SPEED VELOCITY OF AN XConfigureWindow REQUEST?

    /* Is that a SubstructureRedirectMask or a ResizeRedirectMask? */

>WHAT??! HOW AM I SUPPOSED TO KNOW THAT? AAAAUUUGGGHHH!!!!

>(server dumps core & falls into the chasm)

[...]

>X-Windows: Even your dog won't like it.

>X-Windows: Complex non-solutions to simple non-problems.

>X-Windows: The First Fully Modular Software Disaster

Thank you so much. This is the best thing I've read all week. It is truly incredible how many piles of hacks make the modern X11 desktop. Now we have new fun things like high DPI displays too! It's kind of amazing it works at all.

You forgot my favorite one! Xlib is written so badly that there is no graceful way to deal with a connection error to the server - the library gives you one callback to clean up and then it forcibly aborts the process. I looked into why, and its basically because they have no provision for cleanup of failed function calls. If a function can’t return the expected result it would either leave behind a broken internal state of the library or segfault, so they call abort() as a workaround.

If not for this glaring design disaster, it would be possible for a program to attempt re-connecting to a new display server after the previous one crashed. No X11 program has ever done this only because Xlib made it impossible.

Would it be possible to solve this by creating a proxy between the xlib application and the X server? This proxy could re-issue failed requests, or reroute them to a different server. Basically, it would be the error-handling layer, so that all xlib calls always seem to work, from the application's viewpoint.

As a proxy, it could improve error handling across all X applications without any application code changes.

It would be better for life on Earth as we know it if the proxy simply cut you off from the X server, forcing you to find a better window system to use. It's much better to prevent errors from happening in the first place, than to handle them after they happen.

good old times

>sourceforge

I'm glad I haven't used this site in years and I don't plan to change that today.

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