NewExecDriver returns a new DrivePlugin implementation.

PluginConfig is the exec driver factory function registered in the plugin catalog.

PluginID is the exec plugin metadata registered in the plugin catalog.

Config is the driver configuration set by the SetConfig RPC call.

Driver fork/execs tasks using many of the underlying OS's isolation features where configured.

TaskConfig is the driver configuration of a task within a job.

TaskState is the state which is encoded in the handle returned in StartTask.