41.8 Emacs Terminal Emulator

To run a subshell in a terminal emulator, putting its typescript in an Emacs buffer, use M-x term. This creates (or reuses) a buffer named ‘*terminal*’, and runs a subshell with input coming from your keyboard, and output going to that buffer.

The terminal emulator uses Term mode, which has two input modes. In line mode, Term basically acts like Shell mode; see Shell Mode.

In char mode, each character is sent directly to the inferior subshell, as “terminal input.” Any “echoing” of your input is the responsibility of the subshell. The sole exception is the terminal escape character, which by default is C-c (see section Term Mode). Any “terminal output” from the subshell goes into the buffer, advancing point.

Some programs (such as Emacs itself) need to control the appearance on the terminal screen in detail. They do this by sending special control codes. The exact control codes needed vary from terminal to terminal, but nowadays most terminals and terminal emulators (including xterm) understand the ANSI-standard (VT100-style) escape sequences. Term mode recognizes these escape sequences, and handles each one appropriately, changing the buffer so that the appearance of the window matches what it would be on a real terminal. You can actually run Emacs inside an Emacs Term window.

The file name used to load the subshell is determined the same way as for Shell mode. To make multiple terminal emulators, rename the buffer ‘*terminal*’ to something different using M-x rename-uniquely, just as with Shell mode.

Unlike Shell mode, Term mode does not track the current directory by examining your input. But some shells can tell Term what the current directory is. This is done automatically by bash version 1.15 and later.