Function from_cli

pub fn from_cli() -> Result<String, Error>

Returns the host triple of the current rustc using CLI.

Notice that such implementation relies on presence of rustc on the machine where this function is called. Two good places for it are in a build script or in a procedural macro.

Example

fn main() {
    let host = rustc_host::from_cli().unwrap();
    println!("host: {}", host);
}

Implementation details

At the moment of writing, it relies on the output of rustc -vV, which is expected to be nearly in the following format:

rustc 1.66.0 (69f9c33d7 2022-12-12)
binary: rustc
commit-hash: 69f9c33d71c871fc16ac445211281c6e7a340943
commit-date: 2022-12-12
host: x86_64-pc-windows-msvc
release: 1.66.0
LLVM version: 15.0.2

To be precise, it expects a line starting with host: .