Toisc go bhfuil spás seoltaí scoite ag gach próiseas, ní féidir leo athróga a roinnt gan bhac — teastaíonn inter-process communication (IPC) uathu. Cuireann an OS roinnt meicníochtaí ar fáil, éagsúil ó thaobh luais, treo, agus cé acu an n-oibríonn siad trasna meaisíní.
Na príomh-mheicníochtaí
Pipe / FIFO → byte stream, one direction; anonymous pipe = parent↔child, named FIFO = any procs
e.g. ls | grep foo (the shell wires stdout→stdin via a pipe)
Shared memory → both map the SAME physical pages → FASTEST (no copy), but you must
synchronize access yourself (semaphore/mutex)
Message queue → kernel-managed queue of discrete messages; decoupled, preserves boundaries
Socket → bidirectional stream/datagram; UNIX-domain (same host) or TCP/UDP (across network)
Signal → tiny async notification (a number), e.g. SIGINT, SIGTERM — control, not data transfer
