extern kern_return_t ledger_disable_callback(ledger_t ledger, int entry);
extern kern_return_t ledger_enable_callback(ledger_t ledger, int entry);
extern kern_return_t ledger_get_limit(ledger_t ledger, int entry,
ledger_amount_t *limit);
extern kern_return_t ledger_set_limit(ledger_t ledger, int entry,
ledger_amount_t limit, uint8_t warn_level_percentage);
extern kern_return_t ledger_disable_callback(ledger_t ledger, int entry);
extern kern_return_t ledger_enable_callback(ledger_t ledger, int entry);
extern kern_return_t ledger_get_limit(ledger_t ledger, int entry,
ledger_amount_t *limit);
extern kern_return_t ledger_set_limit(ledger_t ledger, int entry,
ledger_amount_t limit, uint8_t warn_level_percentage);