# Function std::env::join_paths

1.0.0 · source ·

    pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>where
        I: IntoIterator<Item = T>,
        T: AsRef<OsStr>,

Expand description

Joins a collection of `Path`s appropriately for the `PATH` environment variable.

## Errors

Returns an `Err` (containing an error message) if one of the input `Path`s contains an invalid character for constructing the `PATH` variable (a double quote on Windows or a colon on Unix).

## Examples

Joining paths on a Unix-like platform:

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

    fn main() -> Result<(), env::JoinPathsError> {
        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(())
    }

Run

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

    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());

Run

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)?;
            env::set_var("PATH", &new_path);
        }

        Ok(())
    }

Run