Vertical Line Markers

Suppose you type a lot in the terminal, and I bet you do. Some commands may have inconveniently long output and you need a way to conveniently scroll the terminal viewport up to the top of that command. This is what this feature is there for. You can easily walk up/down your markers like you'd walk up code folds or markers in VIM or other editors.

Set a mark:

echo -ne "\033[>M"

Example key bindings in Contour:

input_mapping:
    - { mods: [Alt, Shift], key: 'k', mode: '~Alt', action: ScrollMarkUp }
    - { mods: [Alt, Shift], key: 'j', mode: '~Alt', action: ScrollMarkDown }

It is recommended to integrate the marker into your command prompt, such as $PS1 in bash or sh to have automatic markers set.

Integration into ZSH:

zsh is way to configurable to give a fully generic answer here, but to show how you can integrate vertical line markers when using the powerlevel9k, this is what your ~/.zshrc config could contain:

prompt_setmark() {
    echo -ne "%{\033[>M%}"
}
POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(setmark user dir vcs)

Integration into Bash

Bash is usually highly customized to your needs, but the bottom line would be as suggested below. You can create your custom prompt_setmark function that contains \\[ and \\] as enclosing markers for the escape sequence to tell your shell that they do not change the current cursor position, and then use this function in our PS1 environment variable or invoked inside your function assigned to PROMPT_COMMAND.

prompt_setmark() {
    echo -ne "\\[\033[>M\\]"
}

# extending existing PS1
export PS1="`prompt_setmark`${PS1}"