EXTERNAL-PROGRAM enables running programs outside the Lisp process. It is an attempt to make the
RUN-PROGRAM functionality in implementations like SBCL and CCL as portable as possible without sacrificing much in the way of power.
Note: This library is available via Quicklisp.
Here are some of the differences:
RUN(sync) into two separate functions, rather than using a single function with a
WAITparameter that changes the function's specification;
- offers a
REPLACE-ENVIRONMENT-Pparameter that indicates whether provided env vars should build on or replace the current environment.
Read the API documention for details. It’s a bit spartan, but should explain a lot.
Not all functionality is available on all platforms.
EXTERNAL-PROGRAM provides warnings and errors when these limitations are encountered. But I'll try my best to work around them.
There is currently at least some support for:
- Allegro (blocking only)
- Armed Bear (blocking only)
- Clozure CL (née OpenMCL)
In addition to some implementations only providing blocking calls, some don’t use
$PATH – the ones that don’t won’t find bareword commands, you’ll need to use a pathname.