Function libcryptsetup_sys::crypt_activate_by_keyfile_offset

pub unsafe extern "C" fn crypt_activate_by_keyfile_offset(
    cd: *mut crypt_device, 
    name: *const c_char, 
    keyslot: c_int, 
    keyfile: *const c_char, 
    keyfile_size: size_t, 
    keyfile_offset: size_t, 
    flags: u32
) -> c_int