The libudev-sys crate provides declarations and linkage for the libudev C library. Following the
*-sys package conventions, the libudev-sys crate does not define higher-level abstractions over
the native libudev library functions.
In order to use the libudev-sys crate, you must have a Linux system with the libudev library
installed where it can be found by pkg-config. To install libudev on Debian-based Linux
distributions, execute the following command:
sudo apt-get install libudev-dev
libudev is a Linux-specific package. It is not available for Windows, OSX, or other operating
systems.
To link to a cross-compiled version of the native libudev library, it's necessary to set several
environment variables to configure pkg-config to work with a cross-compiler's sysroot. Autotools
Mythbuster has a good explanation of supporting
cross-compilation with pkg-config.
However, Rust's pkg-config build helper doesn't
support calling a $CHOST-prefixed pkg-config. It will always call pkg-config without a prefix.
To cross-compile libudev-sys with the pkg-config build helper, one must define the environment
variables PKG_CONFIG_DIR, PKG_CONFIG_LIBDIR, and PKG_CONFIG_SYSROOT_DIR for the default
pkg-config. It's also necessary to set PKG_CONFIG_ALLOW_CROSS to tell Rust's pkg-config helper
that it's okay to proceed with a cross-compile.
To adapt the pkg-config wrapper in the Autotools Mythbuster guide so that it works with Rust, one
will end up with a script similar to the following:
```sh
SYSROOT=/build/root
export PKGCONFIGDIR= export PKGCONFIGLIBDIR=${SYSROOT}/usr/lib/pkgconfig:${SYSROOT}/usr/share/pkgconfig export PKGCONFIGSYSROOTDIR=${SYSROOT} export PKGCONFIGALLOWCROSS=1
cargo build ```
Add libudev-sys as a dependency in Cargo.toml:
toml
[dependencies]
libudev-sys = "0.1.0"
Import the libudev_sys crate and use the functions as they're defined in the native libudev
library. See the libudev API documention
for more usage information.
rust
extern crate libudev_sys as ffi;
Since libudev-sys does nothing more than export symbols from the native libudev library, the
best source for help is the information already available for the native libudev:
Copyright © 2015 David Cuddeback
Distributed under the MIT License.