fish-shell/doc_src/fish_prompt.txt

\section fish_prompt fish_prompt - define the apperance of the command line prompt

\subsection fish_promt-synopsis Synopsis
<pre>function fish_prompt
    ...
end</pre>

\subsection fish_prompt-description Description

By defining the \c fish_prompt function, the user can choose a custom
prompt. The \c fish_prompt function is executed when the prompt is to
be shown, and the output is used as a prompt.

Please keep in mind that the function is executed by <a
href='./index.html#expand-command-substitution'>command substitution</a> and so, even though on the outside it won't change, it's still possible to locally redefine variables and have the status variable changed.

\subsection fish_prompt-example Example

A simple prompt:

<pre>
function fish_prompt -d "Write out the prompt"
	printf '\%s\@\%s\%s\%s\%s> ' (whoami) (hostname|cut -d . -f 1) (set_color \$fish_color_cwd) (prompt_pwd) (set_color normal)
end
</pre>