281–290 of 414 posts
When requesting pizza delivery from the Domino's site I captured and modified the http request to delete the `crust_type` field. Turns out most of the price was calculated from that so I was getting incredibly cheap pizzas for a while until they found out and invalidated requests without crust selection.
Sounds a little like None Pizza with Left Beef, also on Domino's: https://youtu.be/5yWTPtPYukg
I once needed to install a very large piece of enterprise software in a locked-down enterprise environment. The client had contractually agreed that we would download the software rather than using physical media and for complicated reasons due to IP licensing we were not allowed to install via physical media. However the enterprise IT/infosec folks at the client didn’t like our project and refused to whitelist our u…
So I went back to my hotel room, put on some coffee and spent most of the night writing a bunch of boilerplate code wiring in various methods in apache commons math. The next day I had another meeting with him to discuss something. I chose as an example a function we had quickly knocked up that did a bunch of matrix math. “I thought you said it didn’t do linear algebra?” He said. Felt pretty good to say “Yeah that was yesterday. I just added it”.
Well, I made a horrible mistake. Right after deploying (compiling then manually copying a .class file onto our server), I accidentally lost the source code to all my work. There was no backup of the changes I'd made, and source control didn't have it. All testing was manual - which was a horrible process we went through before every deployment. So if I half remembered my changes, I'd have to manually test everything again and hope I didn't mess anything up.
All I had left was the compiled java .class with my changes in it. I was terrified to even tell my boss given all the work.
Well, I tried decompiling the .class file with my changes in it - but the result was 10k lines of nightmare fuel. How could I find my changes in that? But I also had the java file from a few weeks earlier, before I made my changes. So I compiled the previous version, then decompiled it. Then I diffed the two decompiled source code files. That showed me (in decompiled java form) all the places where I'd made changes, and with some work I managed to figure out what all my changes were.
A few hours later I had re-implemented all my changes in the java source file. I could guarantee I'd done it correctly because the output from the decompiler matched perfectly. So we didn't even need to re-do all our manual testing.
I don't think I ever told my boss.
In theory this gave you a lot of options, but in practice, switching palettes tended to cause "palette flash" where the previous image changed color in a distracting flash.
I was doing a multimedia project that had video in it, and each CODEC had its own built in palette -- one for Cinepak, one for Indeo, etc. Then there were other palettes for the images. If you wanted to display video in a window on a page that had other graphics, you could determine the palette of the CODEC (with some effort) and then use that to dither your graphics. Theoretically they should play nice together, and it worked on some cards, but you'd still get palette flash on other mainstream graphics cards.
I tried every trick I could think of but could not eliminate the flash on every single card until I came up with this hack:
Make a video consisting of a single frame with a 1x1 black pixel, compressed in the desired CODEC, display a black screen for a moment, play that video (which was as fast as could be because it was so tiny) over the screen, then load your image and real video.
The black screen couldn't flash, and when the next screen and video (the real one we wanted to play) came up, the palette was already set correctly. And it worked on every video card.
HDGT26YA
HDGT26YB
HDGT26YC
HDGT26YD
...
Not that big in the grand scheme of things but pretty satisfying for an afternoons work.
Elementary school, Windows 3.x era. School district thought they blocked access to the built-in OS games. Nope, from any program (Wordpad, etc) you could FILE -> OPEN to find/launch/play Minesweeper. Nothing makes an 8-year-old feel more like a "hacker" than subverting school controls to play video games, while also gaining cred with your friends. The good ol' days.
Creating a .bat file and double clicking on it got it loading just fine.
I didn't find any cool tricks to do with it besides just running it.
In my first job I work on a database product in development that leaked memory slowly, leading to crashes after hours of usage. The software was written in C and there were no tools like Purify or Valgrind back then to deal with memory problem. It was a vexing problem that got punted until release time, when it became a show stopper. I looked into the problem and found that the memory allocation used malloc and free.…
After reading an inspiring story in the mid 90s about someone that collected rejection letters for jobs they weren't qualified for (CEO of a national rail carrier etc), I turned to a life built on a similar idea. I applied for jobs I thought I could do, using mostly made-up resume information. If I was scheduled for an interview I would study like mad every waking hour until the interview. My career was absurdly succ…
Sounds better than working as a product manager for 25 years.
In my first job I work on a database product in development that leaked memory slowly, leading to crashes after hours of usage. The software was written in C and there were no tools like Purify or Valgrind back then to deal with memory problem. It was a vexing problem that got punted until release time, when it became a show stopper. I looked into the problem and found that the memory allocation used malloc and free.…
Using the approach you described is extremely effective and low-overhead, and allowed me to actually reproduce the issue (I think in the end it was due some async / race condition issue, because I was using “if map[key]” in a place where I shouldn’t, which actually inserts the key if it’s missing (and thus mutates the map).
Fun times.