With the-config.scm:

-----
(use config)

(node-id         5)
(file-store-path "ugc/")
(database-file   "../db/knodium.sqlite")
(display (customer))
	(let ((x (conc "a " (with-input-from-file "/tmp/ppp" read-line))))
	(with-output-to-file "/tmp/ppp" (lambda () (write-line x))))
;ssl cert file
-----


I see

-----
ding...
Reading...knapp.appReading...knapp.appReading...knapp.app
-----

but I the same /tmp/ppp file as with the-config.scm thus:

-----
(use config)

(node-id         5)
(file-store-path "ugc/")
(database-file   "../db/knodium.sqlite")
(display (customer))
(newline)
	(let ((x (conc "a " (with-input-from-file "/tmp/ppp" read-line))))
	(with-output-to-file "/tmp/ppp" (lambda () (write-line x))))
;ssl cert file
-----