They need to know how to unpack the file and they also need to know to run your magic script of commands after the unpack. However, you can easily create a shell script that contains a file ...

Bash allows you to work with custom file descriptors beyond the standard 0 (stdin), 1 (stdout), and 2 (stderr). You can also ...

About the worst thing you might have to deal with is attempts to fake line endings across Windows and Linux ... to write two shell scripts. One will generate an image file. I cheated in two ...