I’ve used COM (and before that CORBA) but these operate at a different level of abstraction. On VMS calling a Pascal function from FORTRAN “just worked” and the

I’ve used COM (and before that CORBA) but these operate at a different level of abstraction. On VMS calling a Pascal function from FORTRAN “just worked” and then you could pass the return value to a C function or BASIC and it was fine. VMS IPC was done via mailboxes, send a message to a person or a program was the same. Which sounds weird to anyone used to the way Unix does mail, but it worked very well. (Yep, VAX BASIC was a serious language used for real, production applications)