Question about use of uiop:launch-program

[rpgoldman]

py4cl/src/python-process.lisp

Lines 17 to 34 in 601ed20

	(defun python-start (&optional (command *python-command*))
	"Start a new python subprocess
	This sets the global variable *python* to the process handle,
	in addition to returning it.
	COMMAND is a string with the python executable to launch e.g. \"python\"
	By default this is is set to *PYTHON-COMMAND*
	"
	(setf *python*
	(uiop:launch-program
	(concatenate 'string
	"exec "
	command ; Run python executable
	" "
	;; Path *base-pathname* is defined in py4cl.asd
	;; Calculate full path to python script
	(namestring (merge-pathnames #p"py4cl.py" py4cl/config:*base-directory*)))
	:input :stream :output :stream))
	(incf *current-python-process-id*))

Is there some reason for using the shell + exec instead of just using the binary directly? This would be something like the following:

(uiop:launch-program
              (list command 
                      ;; Calculate full path to python script
                      (namestring (merge-pathnames #p"py4cl.py" py4cl/config:*base-directory*)) 
              :input :stream :output :stream))

I would guess that using the shell might introduce some oddities depending on the user's configuration.

Thanks!

[digikar99]

I ended up removing exec in this context in py4cl2 very early on, so I too am curious about if it was important.