atuinsh/atuin · error

Failed to get current PID

Error message

Failed to get current PID

What it means

A panic in Shell::current (atuin-common) when sysinfo's get_current_pid() returns an error, i.e. the platform cannot report Atuin's own process ID. Shell::current walks sysinfo's process table to find its parent process (the shell that invoked Atuin) and derive the shell from its name; the very first step, obtaining its own PID, is unwrapped with expect. It is a platform-support failure in sysinfo, not something config or usage causes — and note the sibling expects after it ('Atuin running with no parent!', process lookup) can equally abort exotic setups.

Source

Thrown at crates/atuin-common/src/shell.rs:41

    #[display("unknown")]
    Unknown,
}

#[derive(Debug, Error, Serialize)]
pub enum ShellError {
    #[error("shell not supported")]
    NotSupported,

    #[error("failed to execute shell command: {0}")]
    ExecError(String),
}

impl Shell {
    pub fn current() -> Shell {
        let sys = System::new_all();

        let process = sys
            .process(get_current_pid().expect("Failed to get current PID"))
            .expect("Process with current pid does not exist");

        let parent = sys
            .process(process.parent().expect("Atuin running with no parent!"))
            .expect("Process with parent pid does not exist");

        let shell = parent.name().trim().to_lowercase();
        let shell = shell.strip_prefix('-').unwrap_or(&shell);

        Shell::from_string(shell.to_string())
    }

    pub fn from_env() -> Shell {
        std::env::var("ATUIN_SHELL").map_or(Shell::Unknown, |shell| {
            Shell::from_string(shell.trim().to_lowercase())
        })
    }

View on GitHub (pinned to 202f6ad98e)

Solutions

  1. Set the ATUIN_SHELL environment variable to your shell name and prefer Shell::from_env(), which reads it without any process-table walk
  2. Run on a platform sysinfo supports (any mainstream Linux/macOS/Windows/BSD)
  3. Fix the sandbox/container so /proc is mounted and readable
  4. In embedding code, call Shell::from_env() or Shell::from_string() instead of Shell::current() to avoid the panic path entirely

Example fix

// before
let shell = Shell::current(); // panics if sysinfo cannot get our PID
// after
let shell = std::env::var("ATUIN_SHELL")
    .map(|s| Shell::from_string(s.trim().to_lowercase()))
    .unwrap_or_else(|_| Shell::current());
Defensive patterns

Strategy: fallback

Validate before calling

// Prefer environment-based detection; only fall back to process introspection
std::env::set_var("ATUIN_SHELL", "zsh"); // set in shell init files before invoking atuin
let shell = Shell::from_env(); // never panics: Unknown when var absent

Type guard

fn shell_detectable() -> bool {
    // sysinfo needs a readable /proc (linux) or supported process API
    cfg!(any(target_os = "linux", target_os = "macos", target_os = "windows", target_os = "freebsd"))
        && std::path::Path::new("/proc").exists() || cfg!(not(target_os = "linux"))
}

Try / catch

// expect() panic: not catchable as an error. Avoid the panic path by preferring
// Shell::from_env() (reads ATUIN_SHELL, returns Shell::Unknown instead of panicking)
// or Shell::from_string(name) when the caller already knows the shell.

Prevention

When it happens

Trigger: Running Shell::current() on a platform/target where sysinfo cannot enumerate processes or provide the current PID (some containers, sandboxes, wasm, or Tier-3 OS targets); typically during shell-hook init or commands that need to detect the invoking shell.

Common situations: Running Atuin inside minimal sandboxes or exotic emulated environments where /proc is absent or process introspection is blocked; cross-compiled builds on unsupported operating systems.

Related errors

AI-assisted analysis of atuinsh/atuin@202f6ad98e (2026-08-16). Data as JSON: /api/errors/91886c19964bd619. Report an issue: GitHub.