fairy-stockfish was just an example. It was derived from Stockfish. I have tested it with several UCI engines, including all Stockfish versions from 12 to 16, Polyfish, Komodo Dragon and others. When exactly the crash occurs varies. This also depends on how the chess engine was compiled. With fairy-stockfish it runs reasonably stable at a depth of 12 half-moves. It "only" crashes every 100th game. But 12 half-moves is far too little to do anything sensible with it.
A buffer overflow was my first assumption. So I installed it in between so that after each move the engine is restarted, FEN is sent and global.output="" is set. Unfortunately, that didn't help. There were also problems because I change the engine in the middle of the game, but I solved that. Now it is called, I send FEN for every move, but it runs through.
My current guess is this: Greater depth means that the engine pauses at some point, so it doesn't send anything. I suspect that because the EXE is not responding, synchronization is lost.
If you give me another contact, Discord or mail, I can also send you screenshots or the current version. It's a pretty big project by now and it would be a shame if it were to fail.
My discord is "samuelvenable". Try downloading the project again and see if the new version of the extension fixes it. I added a new function which allows you to limit the buffer length to a specific number of characters, (including the null byte at the end). For example:
SetBufferLimitForStandardOutput(2048);
...will limit the buffer to 2,048 of the most recent characters.
For readers of this topic, I was able to narrow down the issue further, and it turns out that this is not a bug with the extension/demo itself, but rather a bug with GameMaker. I just tried the extension in a different game engine, a GameMaker clone called STIGMA, I maintain, (my fork of ENIGMA), and it doesn't crash on any platform, not even on Windows. Since both STIGMA and GameMaker rely on identical code for the xProcess extension, this is how we know it is a bug with GameMaker and not my extension. You can download the EXE made with STIGMA yourself if you would like to see for yourself what I am talking about:
https://github.com/time-killer-games/ENIGMA-StockfishChess-Demo/releases/downloa... You will notice if you leave the EXE running for a long time (it has the depth set to 1,000) it won't ever crash. I am going to report this bug to YoYoGames, but it is so specific to my extension and doesn't really effect any other projects, I doubt they will fix it, so no one should hold their breath or be the least bit hopeful about this. Previous download link includes a Windows EXE, macOS APP. Linux ELF, and not to mention there is also the GM81 project file which may be edited and compiled with STIGMA. STIGMA can be downloaded here: https://samuel-venable.itch.io/stigma-development-environment
