[Maxima-discuss] How to suppress the output of lisp function

[z_axis <z_...@16...>]

There is a funtion in utils.lisp as below:
(defun sh (cmd)
  (ccl:run-program "/bin/sh" (list "-c" cmd) :input nil :output *standard-output*))

$fx86cl -n -Q -l utils -e '(progn (m:sh "ls") (ccl:quit))'
works without any junks. However,

$maxima --very-quiet -X '-n -Q' -p utils.lisp --batch-string=':lisp (m:sh "ls");'
will output as below:

Lisp options: (-n -Q)Desktop
HyperSpec
tmp.tex
...
#<EXTERNAL-PROCESS (/bin/sh -c ls)[935] (EXITED : 0) #x385E9896>

Can maxima pretty print it as:

Lisp options: (-n -Q)
Desktop
HyperSpec
tmp.tex
...

Especially suppressing the tail "#<EXTERNAL-PROCESS ...".

Regards!

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e^(π.i) + 1 = 0