acpi_available(1) on Linux
The text ac0f0081ed41, as Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze), Debian 5.0 (Lenny), Debian 4.0 (Etch) shipped it. The page shows this text now.
test whether ACPI subsystem is available