Joins a collection of Paths appropriately for the PATH environment variable.

Errors

Returns an Err (containing an error message) if one of the input Paths contains an invalid character for constructing the PATH variable (a double quote on Windows or a colon on Unix), or if the system does not have a PATH-like variable (e.g. UEFI or WASI).

Examples

Joining paths on a Unix-like platform:

use std::env;
use std::ffi::OsString;
use std::path::Path;

fn main() -> Result<(), env::JoinPathsError> {
# if cfg!(unix) {
    let paths = [Path::new("/bin"), Path::new("/usr/bin")];
    let path_os_string = env::join_paths(paths.iter())?;
    assert_eq!(path_os_string, OsString::from("/bin:/usr/bin"));
# }
    Ok(())
}

Joining a path containing a colon on a Unix-like platform results in an error:

# if cfg!(unix) {
use std::env;
use std::path::Path;

let paths = [Path::new("/bin"), Path::new("/usr/bi:n")];
assert!(env::join_paths(paths.iter()).is_err());
# }

Using env::join_paths() with env::split_paths() to append an item to the PATH environment variable:

use std::env;
use std::path::PathBuf;

fn main() -> Result<(), env::JoinPathsError> {
    if let Some(path) = env::var_os("PATH") {
        let mut paths = env::split_paths(&path).collect::<Vec<_>>();
        paths.push(PathBuf::from("/home/xyz/bin"));
        let new_path = env::join_paths(paths)?;
        unsafe { env::set_var("PATH", &new_path); }
    }

    Ok(())
}