Programming Erlang, 2nd Edition

Chapter 15Interfacing Techniques

Building systems often involves interfacing applications written in different programming languages with our system. We might use C for efficiency or writing low-level hardware drivers, or we might want to integrate a library written in Java or Ruby or some other programming language. We can interface foreign language programs to Erlang in a number of ways.

• By running the programs outside the Erlang virtual machine in an external operating system process. This is the safe way of doing things. If the foreign language code is incorrect, it will not crash the Erlang system. Erlang controls the external process through a device called a port and communicates with the external process through a byte-oriented communication ...