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NOTE: This project is unmaintained

CloudABI is no longer being maintained. It was an awesome experiment, but it never got enough traction to be sustainable. If you like the idea behind CloudABI, please consider looking into the WebAssembly System Interface (WASI). WASI's design has been inspired by CloudABI.

The author of CloudABI (Ed Schouten) would like to thank all of the people who contributed to this project. Let's hope CloudABI lives on in spirit and influences the way software is designed in the future!

Nuxi CloudABI utilities

This package contains a number of libraries and utilities that can be used to easily start CloudABI programs.

The libcloudabi library provides a native port of the program_exec() function. This is the function that can normally be used by CloudABI programs to start new executables, similar to the POSIX fexecve() function.

Whereas fexecve() uses simple string command line arguments, program_exec() uses a YAML-like tree structure, called argdata. What is special about argdata, is that file descriptors are a native primitive data type; they can be attached as leaves to the tree directly. This makes the way of inheriting file descriptors during process execution a lot more structured. It replaces concepts like close-on-exec flags entirely.

To ensure that this implementation of program_exec() conforms to CloudABI's safety requirements (i.e., that it is safe to run untrusted programs, and that file descriptors that are not referenced by the argdata structure are not leaked into new processes), program_exec() depends on a small proxy executable called cloudabi-reexec. This package ships with prebuilt copies that were built by the CloudABI Ports Collection.

Finally, this package provides the cloudabi-run utility, which is built on top of libcloudabi. This utility reads a YAML file from stdin, converts it to an argdata, and uses that to start a CloudABI executable. It provides some special tags to automatically open files and network connections. cloudabi-run also includes an emulator that can be used to run CloudABI executables on operating systems for which no native support is provided. Please refer to cloudabi-run's manual page for more details and examples.

More details about CloudABI can be found on Nuxi's company webpage.