using pipes to channel file i/o to another process

Question

Just started learning/using pipes and was wondering how to route file output of an application into a pipe so that another application can use it.

To be exact, I want t

Answer 1

ffmpeg can also read from stdin and write to stdout like this:

ffmpeg -i pipe:0 -f wav pipe:1

where 0 and 1 are the standard POSIX file descriptors.