Show HN: Threadprocs – executables sharing one address space (0-copy pointers)

Summary

This repository contains experimental code for thread-like processes, or multiple programs running in a shared address space. Each threadproc behaves like a process with its own executable, globals, libc instance, etc, but pointers are valid across threadprocs. This blends the Posix process model with the Posix multi-threading programming model, and enables things like zero-copy access to pointer-based data structures. All Markdown files were written by hand. See tproc-actors for one possible application framework building on top of threadprocs. The code for the demoed programs is at example/sharedstr/allocstr.cpp and example/sharedstr/printstr.cpp, and neither contains any magic (/proc/[pid]/mem, etc), nor awareness of the server and launcher. allocstr reads input, and copies it into a new std::string, and prints &newstring to console. printstr reads a pointer as hex text, and prints whatever std::string it finds there. demo.mp4 The server utility "hosts" a virtual address space, and by using launcher to start programs, those launched programs coexist in the hosted address space. Applications can share pointers in the virtual address space through some out-of-band mechanism (Demo uses copy/paste, dummy_server/client uses sockets, libtproc provides server-global scratch space), and then directly dereference those pointers, as they're valid in the shared address space. libtproc provides basic detection of execution as a threadproc, and allows hosted threadprocs to access a "server-global" scratch space. Applications can build tooling using this space to implement service discovery and bootstrap shared memory-backed IPC. This is implemented by adding another entry to the threadproc auxv. tproc-actors uses this space to advertise per-threadproc actor registries. Use Linux on aarch64 or x86_64; other architectures are not supported. This was developed in a VM running Debian on a Macbook Air M1, and also tested in a Debian x86_64 Github Codespace using the .devcontainer/...