Function flake_lock_flags_set_mode_write_as_needed 

pub unsafe extern "C" fn flake_lock_flags_set_mode_write_as_needed(
    context: *mut c_context,
    flags: *mut flake_lock_flags,
) -> err

@brief Put the lock flags in a mode that updates the lock file on disk, if needed. @param[out] context Optional, stores error information @param[in] flags The flags to modify @param[in] update Whether to allow updates

This will cause nix_flake_lock to update the lock file on disk, if needed.