Here is the code with two things I tried as the ":filter" in ": my-pass-it-on-filter":

(defun my-pass-it-on-sentinel (proc _msg)
  "Process entire output of PROC line-wise."
  (when (and (eq (process-status proc) 'exit)
             (zerop (process-exit-status proc))
             (buffer-live-p (process-buffer proc)))
    (with-current-buffer (process-buffer proc)
      (mapc #'(lambda (x) x) (split-string (buffer-string) "\n" t))

(defun my-pass-it-on-filter (filePath proc str)
  "Process each line produced by PROC in STR."
  (when (buffer-live-p (process-buffer proc))
    (with-current-buffer (process-buffer proc)
      (insert str)
      (goto-char (point-min))
      (while (progn (skip-chars-forward "^\n")
                    (not (eobp)))
        ((lambda (line) (progn ((message ">>> %s" line)) (ignore-errors line))) (delete-and-extract-region (point-min) (point)))
        (delete-char 1)))))
(make-process :name "my-proc2"
              :buffer " *my-proc2*"
              :command '("sh" "-c" "echo 1 && sleep 5 && echo 2")
              :connection-type 'pipe
              ;; :filter #'(funcall 'my-pass-it-on-filter "/tmp/mytmp")
              :filter #'(apply-partially 'my-pass-it-on-filter "/tmp/mytmp")
              :sentinel #'my-pass-it-on-sentinel)
  • 1
    This was also asked and answered on [email protected]. Mentioning that in case there is followup there that readers here might be interested in.
    – Drew
    Commented Oct 9, 2018 at 18:56

1 Answer 1


You almost have it: drop the quote from the apply-partially form so that it reads:

:filter (apply-partially 'my-pass-it-on-filter "/tmp/mytmp") 

The point is that apply-partially returns the function you want.

While we are here, the message form has an extra sets of parens around it.

  • Thanks, that worked! Now on to my other issues :)
    – codygman
    Commented Oct 10, 2018 at 4:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.