nikivdev/code · error · anyhow::Error

Port 80 is already in use by '{}'. Stop that listener, then

Error message

Port 80 is already in use by '{}'. Stop that listener, then retry `f domains up`.

What it means

Error "Port 80 is already in use by '{}'. Stop that listener, then retry `f domains up`." thrown in nikivdev/code.

Source

Thrown at src/domains.rs:548

fn assert_no_port_80_conflict() -> Result<()> {
    if let Some(owner) = docker_container_owning_port_80()? {
        if owner != PROXY_CONTAINER_NAME {
            bail!(
                "Port 80 is already owned by docker container '{}'. Stop it first (for example: docker stop {}).",
                owner,
                owner
            );
        }
        return Ok(());
    }

    if proxy_is_running()? {
        return Ok(());
    }

    if let Some(listener) = port_80_listener_summary()? {
        bail!(
            "Port 80 is already in use by '{}'. Stop that listener, then retry `f domains up`.",
            listener
        );
    }
    Ok(())
}

fn port_80_listener_summary() -> Result<Option<String>> {
    if which::which("lsof").is_err() {
        return Ok(None);
    }
    let output = Command::new("lsof")
        .args(["-nP", "-iTCP:80", "-sTCP:LISTEN"])
        .output()
        .context("Failed to inspect port 80 listeners")?;
    if !output.status.success() {
        return Ok(None);
    }

View on GitHub (pinned to a747e741ae)

When it happens

Trigger: Thrown at src/domains.rs:548 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of nikivdev/code@a747e741ae (2026-09-01). Data as JSON: /api/errors/8259bdd7d12972c4. Report an issue: GitHub.