Writing Common Lisp code that executes from the command line, but not inside the interpreter

Question

When writing Common Lisp code, I use SLIME. In particular, I compile the buffer containing definitions of functions by using C-C C-k, and then switch to the REPL to run thos

Answer 1

I had the same question and I have just stumbled upon this discussion. At least with sbcl it seems I can use (sb-ext:posix-getenv "_"). When run in slime it returns /usr/bin/emacs (or whatever the path to emacs is) and otherwise the command I use to invoke the script. So it is always possible to differentiate between slime and script invocation until you're an emacs contributor :)

If you want to get the full pathname of the script you are invoking, you can use (truename (sb-ext:posix-getenv "_")). However, when run from slime it will return the effective emacs pathname, e.g. /usr/bin/emacs-24.5, so this might be less convenient.