openai/codex · error · anyhow::Error

OpenMutexW failed: {err}

Error message

OpenMutexW failed: {err}

What it means

Error "OpenMutexW failed: {err}" thrown in openai/codex.

Source

Thrown at codex-rs/windows-sandbox-rs/src/bin/setup_main/win/read_acl_mutex.rs:37

impl Drop for ReadAclMutexGuard {
    fn drop(&mut self) {
        unsafe {
            let _ = ReleaseMutex(self.handle);
            CloseHandle(self.handle);
        }
    }
}

pub(super) fn read_acl_mutex_exists() -> Result<bool> {
    let name = to_wide(OsStr::new(READ_ACL_MUTEX_NAME));
    let handle = unsafe { OpenMutexW(MUTEX_ALL_ACCESS, 0, name.as_ptr()) };
    if handle == 0 {
        let err = unsafe { GetLastError() };
        if err == ERROR_FILE_NOT_FOUND {
            return Ok(false);
        }
        return Err(anyhow::anyhow!("OpenMutexW failed: {err}"));
    }
    unsafe {
        CloseHandle(handle);
    }
    Ok(true)
}

pub(super) fn acquire_read_acl_mutex() -> Result<Option<ReadAclMutexGuard>> {
    let name = to_wide(OsStr::new(READ_ACL_MUTEX_NAME));
    let handle = unsafe { CreateMutexW(std::ptr::null_mut(), 1, name.as_ptr()) };
    if handle == 0 {
        return Err(anyhow::anyhow!("CreateMutexW failed: {}", unsafe {
            GetLastError()
        }));
    }
    let err = unsafe { GetLastError() };
    if err == ERROR_ALREADY_EXISTS {
        unsafe {

View on GitHub (pinned to 339751715c)

When it happens

Trigger: Thrown at codex-rs/windows-sandbox-rs/src/bin/setup_main/win/read_acl_mutex.rs:37 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of openai/codex@339751715c (2026-08-25). Data as JSON: /api/errors/0d566b17a966a4d0. Report an issue: GitHub.