libace-6.4.5 6.4.5+dfsg-1build4 (armhf binary) in ubuntu focal

 This package contains the ADAPTIVE Communication Environment (ACE)
 framework.
 .
 It provides platform independent C++ wrappers for all forms of IPC,
 thread- and process-management routines, and much more.
 .
 Moreover, it defines patterns for common communication tasks.
  * Reactor: handles event demultiplexing and dispatching
  * Proactor: for asynchronous I/O driven programs