rust processes cli

std::process::Command for spawning external processes

Marcus Chen Jan 2026

1 tab

use std::process::Command;

fn main() -> std::io::Result<()> {
    let output = Command::new("ls")
        .arg("-la")
        .output()?;

    if output.status.success() {
        let stdout = String::from_utf8_lossy(&output.stdout);
        println!("{}", stdout);
    } else {
        eprintln!("Command failed");
    }
    Ok(())
}

1 file · rust Explain with highlit

std::process::Command runs external programs and captures their output. I use it for CLI tools that wrap other commands, build scripts, or integration tests. Methods like .arg(), .env(), and .current_dir() configure the process. .output() runs and waits, returning stdout/stderr. .spawn() starts the process without waiting. For streaming output, use .stdout(Stdio::piped()) and read from the child's handles. Always check the exit status. I use Command for running formatters, compilers, or shell scripts from Rust. It's safer than shell-ing out because you control arguments explicitly, avoiding injection vulnerabilities.