Linux · Emacs

You want to search and replace across a file in Emacs, and later do it with regex capture groups. Which command starts each, and what placeholders reference the matched text in the replacement?

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More in Emacs

The Emacs name is often mocked as "Escape Meta Alt Control Shift" because of its dense key sequences. What does the acronym actually stand for, and what is Emacs beyond a text editor?

In Emacs, both loading and saving a file start with the same two-key prefix. What are the three core commands for opening a file, saving it, and saving it under a new name?

You mistype a keystroke and get a menu, then hit Ctrl+X Ctrl+C by accident with unsaved work. How do you exit Emacs, and what limit does its undo have?

You started typing an Emacs command, or hit Esc by mistake, and Emacs is now waiting for more input. How do you cancel out of a half-entered command?

A newcomer wants Emacs to teach itself and to look up what a key does. Which help commands start the built-in tutorial, list all key bindings, and describe a command?

You open a .c file and Emacs auto-indents lines in ways you don't want. What is the rule about how many major vs minor modes can be active, and how do you fall back to a plain mode?

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