Emacs: Messages Buffer

What is Messages Buffer

Messages buffer is a special buffer. It displays command outputs or warning and errors.

Switch to the Messages Buffer

view-echo-area-messages 【Ctrl+h e】

switch to the *Messages* buffer.

Name of Messages Buffer

Messages buffer has a buffer name of *Messages*. You can switch to it by any buffer switch commands. 〔see Switch Buffer〕

Special Behavior of the Messages Buffer

• The messages buffer automatically truncates the top entries when the buffer reaches some size (see variable messages-buffer-max-lines 〔see Show Variable Value and Doc〕).
• When a string is repeated many times, it automatically condenses the repeated lines.
• If a string is a huge line, the line is truncated automatically.

Example, the following prints “yay [19 times]” instead of the “yay” line for 19 times.

;; print a line many times
(setq xx 1)
(while (< xx 20)
  (message "yay")
  (setq xx (1+ xx))
  )
(switch-to-buffer "*Messages*")

Reference

• Displaying Messages (ELISP Manual)