vosk-rs

• Recommended: Create a build script and provide cargo with the path to the libraries
• Use the RUSTFLAGS environment variable to provide the path to the variables like so: RUSTFLAGS=-L/path/to/the/libraries with cargo:rustc-link-search or cargo:rustc-link-lib.
• Make the vosk library accessible system or user-wide:
  • Windows: Move the libraries to a directory in your PATH environment variable.
  • Linux: Move them to /usr/local/lib, /usr/lib or set the LIBRARY_PATH environment variable to the directory containing the libraries.

Although the approaches are equivalent, using a build script is more convenient because it does not require the developer to remember a terminal command or change anything outside the project scope.

Using static libraries (macOS-only, targeting iOS)

• Extract the correct non-fat file (also called thin file) from the static fat file (libvosk.a) for each architecture you would like to support.
• Mark your crate type as staticlib.
• Create a build script and provide cargo with the path to the libraries with cargo:rustc-link-search= and cargo:rustc-link-lib=static=.

Troubleshooting

In real-world scenarios, one will use Rust to cross compile a library (e.g. Android and iOS). Therefore, we need both cdylib as well as the staticlib as crate-type. If you compile as usual with cargo build (e.g.: cargo build --target aarch64-apple-ios --release) it will not work, because cargo tries to build the dylib as well. Fortunately, since rust 1.64, there is a new option for rustc in the stable channel. Because of this, the following will work: cargo rustc --crate-type staticlib --lib --target aarch64-apple-ios --release

Execution

Executables compiled with a dynamic lib must have access to the vosk library at runtime. Executables compiled with a statically compiled library do not.

Using dynamic libraries

Do either of the following:

• Recommended: Copy the libraries to the root of the executable (target/<cargo profile name> by default). It is recommended that you use a tool such as cargo-make to automate moving the libraries from another, more practical, directory to the destination during build.
• Make the vosk library accessible system or user-wide:
  • Windows: Move the libraries to a directory in your PATH environment variable.
  • Linux: Move them to /usr/local/lib, /usr/lib or set the LD_LIBRARY_PATH environment variable to the directory containing the libraries. Note: LD_LIBRARY_PATH is not the same as LIBRARY_PATH mentioned in the compilation step.

Using static libraries (iOS-only)

• Add the compiled .a library (or libraries if you would like to support more than one architecture) to your iOS project
• Set Enable Bitcode to no for your target
• Add the Accelerate Framework from the iOS SDK to your project
• Depending on your library and use case, you have to write some C -> Objective-C -> Swift glue code.