## artd

artd is a component of ART Service. It is a shim service to do tasks that
require elevated permissions that are not available to system_server, such as
manipulation of the file system and invoking dex2oat. It publishes a binder
interface that is internal to ART service's Java code. When it invokes other
binaries, it passes input and output files as FDs and drops capability before
exec.

### System properties

artd can be controlled by the system properties listed below. Note that the list
doesn't include options passed to dex2oat and other processes.

- `dalvik.vm.artd-verbose`: Log verbosity of the artd process. The syntax is the
  same as the runtime's `-verbose` flag.

### The `--pre-reboot` flag

artd can be run in Pre-reboot mode through the `--pre-reboot` flag. The
Pre-reboot mode is for generating outputs for Pre-reboot Dexopt. The flag does
not change the actual behavior, but only affects the service name, the log tag,
a few return checks, etc. Note that how artd addresses input files and output
files is solely determined by AIDL arguments and is **not** affected by the
`--pre-reboot` flag.