0156d68f0c
This is a reimplementation of Io.Threaded that fixes the issues highlighted in the recent Zulip discussion. It's poorly tested but it does successfully run to completion the litmust test example that I offered in the discussion. This implementation has the following key design decisions: - `t.cpu_count` is used as the threadpool size. - `t.concurrency_limit` is used as the maximum number of "burst, one-shot" threads that can be spawned by `io.concurrent` past `t.cpu_count`. - `t.available_thread_count` is the number of threads in the pool that is not currently busy with work (the bookkeeping happens in the worker function). - `t.one_shot_thread_count` is the number of active threads that were spawned by `io.concurrent` past `t.cpu_count`. In this implementation: - `io.async` first tries to decrement `t.available_thread_count`. If there are no threads available, it tries to spawn a new one if possible, otherwise it runs the task immediately. - `io.concurrent` first tries to use a thread in the pool same as `io.async`, but on failure (no available threads and pool size limit reached) it tries to spawn a new one-shot thread. One shot threads run a different main function that just executes one task, decrements the number of active one shot threads, and then exits. A relevant future improvement is to have one-shot threads stay on for a few seconds (and potentially pick up a new task) to amortize spawning costs. |
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| .forgejo/workflows | ||
| .github | ||
| ci | ||
| cmake | ||
| doc | ||
| lib | ||
| src | ||
| stage1 | ||
| test | ||
| tools | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| bootstrap.c | ||
| build.zig | ||
| build.zig.zon | ||
| CMakeLists.txt | ||
| LICENSE | ||
| README.md | ||
A general-purpose programming language and toolchain for maintaining robust, optimal, and reusable software.
Documentation
If you are looking at this README file in a source tree, please refer to the Release Notes, Language Reference, or Standard Library Documentation corresponding to the version of Zig that you are using by following the appropriate link on the download page.
Otherwise, you're looking at a release of Zig, so you can find the language
reference at doc/langref.html, and the standard library documentation by
running zig std, which will open a browser tab.
Installation
A Zig installation is composed of two things:
- The Zig executable
- The lib/ directory
At runtime, the executable searches up the file system for the lib/ directory, relative to itself:
- lib/
- lib/zig/
- ../lib/
- ../lib/zig/
- (and so on)
In other words, you can unpack a release of Zig anywhere, and then begin
using it immediately. There is no need to install it globally, although this
mechanism supports that use case too (i.e. /usr/bin/zig and /usr/lib/zig/).
Building from Source
Ensure you have the required dependencies:
- CMake >= 3.15
- System C/C++ Toolchain
- LLVM, Clang, LLD development libraries == 21.x
Then it is the standard CMake build process:
mkdir build
cd build
cmake ..
make install
For more options, tips, and troubleshooting, please see the Building Zig From Source page on the wiki.
Building from Source without LLVM
In this case, the only system dependency is a C compiler.
cc -o bootstrap bootstrap.c
./bootstrap
This produces a zig2 executable in the current working directory. This is a
"stage2" build of the compiler,
without LLVM extensions, and is
therefore lacking these features:
- Release mode optimizations
- Some ELF linking features
- Some COFF/PE linking features
- Some WebAssembly linking features
- Ability to create static archives from object files
- Ability to compile assembly files
- Ability to compile C, C++, Objective-C, and Objective-C++ files
Even when built this way, Zig provides an LLVM backend that produces bitcode files, which may be optimized and compiled into object files via a system Clang package. This can be used to produce system packages of Zig applications without the Zig package dependency on LLVM.
Contributing
Zig is Free and Open Source Software. We welcome bug reports and patches from everyone. However, keep in mind that Zig governance is BDFN (Benevolent Dictator For Now) which means that Andrew Kelley has final say on the design and implementation of everything.
One of the best ways you can contribute to Zig is to start using it for an open-source personal project.
This leads to discovering bugs and helps flesh out use cases, which lead to further design iterations of Zig. Importantly, each issue found this way comes with real world motivations, making it straightforward to explain the reasoning behind proposals and feature requests.
You will be taken much more seriously on the issue tracker if you have a personal project that uses Zig.
The issue label Contributor Friendly exists to help you find issues that are limited in scope and/or knowledge of Zig internals.
Please note that issues labeled Proposal but do not also have the Accepted label are still under consideration, and efforts to implement such a proposal have a high risk of being wasted. If you are interested in a proposal which is still under consideration, please express your interest in the issue tracker, providing extra insights and considerations that others have not yet expressed. The most highly regarded argument in such a discussion is a real world use case.
For more tips, please see the Contributing page on the wiki.
Community
The Zig community is decentralized. Anyone is free to start and maintain their own space for Zig users to gather. There is no concept of "official" or "unofficial". Each gathering place has its own moderators and rules. Users are encouraged to be aware of the social structures of the spaces they inhabit, and work purposefully to facilitate spaces that align with their values.
Please see the Community wiki page for a public listing of social spaces.