Pretty prompt and logging for demos

A "show the recent prompt history for use in demos and teaching". It has some features not found in all similar tools:

• Show the command in the history before it exits. For long running commands like those that open the editor, watchers need to see the command before it returns back to the shell.
• Also adjust the prompt appearance and color.
• Color the command being typed in addition to the prompt itself.
• Updates the window title bar with the machine name and the working directory (saving space in the prompt itself).
• Logs to a separate file. Recommended to open another terminal (with a smaller font size) to tail -f demos.out.
• Compatible with bash/zsh. Simple, pure shell.
• Compatible with fish (source prompt-log.fish instead)

Installation

Clone the repository, or copy prompt-log.sh locally. It's a single-file script.

source prompt-log.sh (this could even be within your shell startup scripts - the source-ing alone does not change anything).

Make sure you configure your terminal where you can switch to light-background dark-text. It's designed for that (but could be configured by editing the file).

One more step on macOS

To run prompt-log on macOS, we need to install two additional packages that provide macOS with some GNU/Linux functionality. To do this you can use Homebrew and install coreutils and the watch command:

brew install coreutils watch

Background: prompt-log uses readlink to get the absolute path of the output file before it is actually written (cf. Usage). On macOS, we need to get around the fact that its native version of readlink needs the file to exist and also uses different command-line options. prompt-log will check your operation system and will choose to use greadlink on macOS instead of readlink.

Usage

1. Run the shell alias prompt-log [file] to start the logging (this permanently changes the shell prompt and so on). Logs are written to ~/demos.out if [file] is not given.

2. Make sure to type at least one command, so the file gets created.

3. Open a different terminal window and use watch to monitor the contents of [file].

   watch tail [file]
   

Status and development

Under semi-active development, but you might expect to have to modify the source to work on other computers. Please contribute.

See also

• https://coderefinery.org/manuals/instructor-tech-setup/ lists more things to do for a clear screenshare and lists some other options for history logging.