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Read the project’s introduction
Overview
libuv is a multi-platform support library with a focus on asynchronous I/O. It
was primarily developed for use by Node.js, but it's also
used by Luvit, Julia,
uvloop, and others.
Feature highlights
Full-featured event loop backed by epoll, kqueue, IOCP, event ports.
Asynchronous TCP and UDP sockets
Asynchronous DNS resolution
Asynchronous file and file system operations
File system events
ANSI escape code controlled TTY
IPC with socket sharing, using Unix domain sockets or named pipes (Windows)
Child processes
Thread pool
Signal handling
High resolution clock
Threading and synchronization primitives
Versioning
Starting with version 1.0.0 libuv follows the semantic versioning
scheme. The API change and backwards compatibility rules are those indicated by
SemVer. libuv will keep a stable ABI across major releases.
The ABI/API changes can be tracked here.
Licensing
libuv is licensed under the MIT license. Check the LICENSE and
LICENSE-extra files.
The documentation is licensed under the CC BY 4.0 license. Check the
LICENSE-docs file.
Community
Support
Mailing list
Documentation
Official documentation
Located in the docs/ subdirectory. It uses the Sphinx
framework, which makes it possible to build the documentation in multiple
formats.
Show different supported building options:
$ make help
Build documentation as HTML:
$ make html
Build documentation as HTML and live reload it when it changes (this requires
sphinx-autobuild to be installed and is only supported on Unix):
$ make livehtml
Build documentation as man pages:
$ make man
Build documentation as ePub:
$ make epub
NOTE: Windows users need to use make.bat instead of plain 'make'.
Documentation can be browsed online here.
The tests and benchmarks
also serve as API specification and usage examples.
Other resources
LXJS 2012 talk
— High-level introductory talk about libuv.
libuv-dox
— Documenting types and methods of libuv, mostly by reading uv.h.
learnuv
— Learn uv for fun and profit, a self guided workshop to libuv.
These resources are not handled by libuv maintainers and might be out of
date. Please verify it before opening new issues.
Downloading
libuv can be downloaded either from the
GitHub repository
or from the downloads site.
Before verifying the git tags or signature files, importing the relevant keys
is necessary. Key IDs are listed in the
MAINTAINERS
file, but are also available as git blob objects for easier use.
Importing a key the usual way:
$ gpg --keyserver pool.sks-keyservers.net --recv-keys AE9BC059
Importing a key from a git blob object:
$ git show pubkey-saghul | gpg --import
Verifying releases
Git tags are signed with the developer's key, they can be verified as follows:
$ git verify-tag v1.6.1
Starting with libuv 1.7.0, the tarballs stored in the
downloads site are signed and an accompanying
signature file sit alongside each. Once both the release tarball and the
signature file are downloaded, the file can be verified as follows:
$ gpg --verify libuv-1.7.0.tar.gz.sign
Build Instructions
For UNIX-like platforms, including macOS, there are two build methods:
autotools or CMake.
For Windows, CMake is the only supported build method and has the
following prerequisites:
Details
One of:
Visual C++ Build Tools
Visual Studio 2015 Update 3, all editions
including the Community edition (remember to select
"Common Tools for Visual C++ 2015" feature during installation).
Visual Studio 2017, any edition (including the Build Tools SKU).
Required Components: "MSbuild", "VC++ 2017 v141 toolset" and one of the
Windows SDKs (10 or 8.1).
Basic Unix tools required for some tests,
Git for Windows includes Git Bash
and tools which can be included in the global PATH.
To build with autotools:
$ sh autogen.sh
$ ./configure
$ make
$ make check
$ make install
To build with CMake:
$ cmake -B build -DBUILD_TESTING=ON # generate project with tests
$ cmake --build build # add `-j <n>` with cmake >= 3.12
# Run tests:
$ (cd build && ctest -C Debug --output-on-failure)
# Or manually run tests:
$ build/uv_run_tests # shared library build
$ build/uv_run_tests_a # static library build
To cross-compile with CMake (unsupported but generally works):
$ cmake ../.. \
-DCMAKE_SYSTEM_NAME=Windows \
-DCMAKE_SYSTEM_VERSION=6.1 \
-DCMAKE_C_COMPILER=i686-w64-mingw32-gcc
Install with Homebrew
$ brew install --HEAD libuv
Note to macOS users:
Make sure that you specify the architecture you wish to build for in the
"ARCHS" flag. You can specify more than one by delimiting with a space
(e.g. "x86_64 i386").
Install with vcpkg
$ git clone https://github.com/microsoft/vcpkg.git
$ ./bootstrap-vcpkg.bat # for powershell
$ ./bootstrap-vcpkg.sh # for bash
$ ./vcpkg install libuv
Install with Conan
You can install pre-built binaries for libuv or build it from source using Conan. Use the following command:
conan install --requires="libuv/[*]" --build=missing
The libuv Conan recipe is kept up to date by Conan maintainers and community contributors.
If the version is out of date, please create an issue or pull request on the ConanCenterIndex repository.
Running tests
Some tests are timing sensitive. Relaxing test timeouts may be necessary
on slow or overloaded machines:
$ env UV_TEST_TIMEOUT_MULTIPLIER=2 build/uv_run_tests # 10s instead of 5s
Run one test
The list of all tests is in test/test-list.h.
This invocation will cause the test driver to fork and execute TEST_NAME in
a child process:
$ build/uv_run_tests_a TEST_NAME
This invocation will cause the test driver to execute the test in
the same process:
$ build/uv_run_tests_a TEST_NAME TEST_NAME
Debugging tools
When running the test from within the test driver process
(build/uv_run_tests_a TEST_NAME TEST_NAME), tools like gdb and valgrind
work normally.
When running the test from a child of the test driver process
(build/uv_run_tests_a TEST_NAME), use these tools in a fork-aware manne
Read the full README on GitHub