Formatting the Prompt
It is possible to truncate your prompt to fit into a fixed amount of
space. man zshmisc for details, and look under the
section PROMPT EXPANSION.
Additonal formatting escapes
There are some additional '%' escape sequences that control formatting
of the prompt text that zsh displays:
%U Start underline mode
%u Stop underline mode
%B Start boldface mode
%b Stop boldface mode
%S Start standout mode
%s Stop standout mode
%{...%}
Include a string as a literal escape sequence. The
string within the braces should not change the cursor
position. Brace pairs can nest. This can be used to put
color in your prompt. (See below)
A Quick Note
If you would like to use the current history event number in your
prompt without needing a % escape sequence, make sure to turn on the
PROMPT_BANG shell option. This allows you to use
! (bang) in your prompt strings for the current history
event number. If you would like an actual ! to be
displayed in your prompt, use !! in your prompt string.