# top_system_uid Return the highest uid treated as a system account for ancestor ownership checks. ## Synopsis ```perl my $uid = File::Temp::top_system_uid(); ``` ## What you get back The integer `0` (root). ## Differences from upstream - Upstream defaults this value to `10`; pperl returns `0` because the elevated safety levels that consume it are not implemented. Covered by `t/81-xs-native/File-Temp/*.t`. ## See also - `safe_level` — the setting this value participates in.