The avconv utility can be made to work in 'the Unix way' by specifying stdin and/or stdout instead of filenames for the input and output respectively. See: http://libav.org/avconv.html#pipe
Example:
cat input.ts | avconv -i pipe:0 -f mp4 -movflags frag_keyframe pipe:1 | cat > output.mp4
Using node's require('child_process').spawn()
, we can pipe streams of video data through avconv's stdin and stdout and thus Stream All The Things.
var fs = require('fs');