pub fn harden_process_dumpable() -> Result<(), String>Expand description
Marks the current process non-dumpable so no same-UID process — including its own
shell descendants — can read this process’s /proc/<pid>/environ.
Must be called as the first statement of main() in every binary that links this
crate and can reach execute_shell, before any argument parsing or subprocess-capable
code runs. A future binary that links capsule-runtime and reaches execute_shell
inherits the same obligation.
Covers this process for its entire life and nothing else. The spawned shell-tool child
re-enables its own flag from pre_exec — see this module’s header for why that is required
and what it trades away.
No-op on non-Linux targets: /proc/<pid>/environ and prctl(2) don’t exist there,
so there is no side channel to close.