From Newsgroup: comp.lang.lisp

(defun sort-file-lines (input-file output-file)
(with-open-file (instream input-file :direction :input)
(with-open-file (outstream output-file :direction :output)
(dolist (line (sort (loop for line = (read-line instream nil nil)
while line
collect line)
#'string-lessp))
(write-line line outstream)))))

Gauche Scheme:

(use file.util)

(define (sort-file-lines in-file out-file)
(with-output-to-file out-file
(lambda ()
(for-each print (sort (file->string-list in-file))))))

(sort-file-lines "data.bak" "junk")
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