To automatically open output in a pager when it exceeds the screen height in Zsh, you can use a shell function that wraps commands and pipes their output to a pager if necessary. Here's how you can implement this:

1. Add the following function to your .zshrc file:

auto_pager() {
  local cmd="$1"
  shift
  $cmd "$@" | {
    if [ $(tput lines) -lt $(/usr/bin/env wc -l) ]; then
      $PAGER
    else
      cat
    fi
  }
}

2. Create aliases for commands you want to automatically page:

alias ls='auto_pager ls'
alias grep='auto_pager grep'
alias tree='auto_pager tree'
# Add more aliases as needed

This solution works as follows:

1. The auto_pager function takes a command and its arguments.
2. It runs the command and pipes its output to a subshell.
3. Inside the subshell, it compares the number of lines in the output to the terminal height.
4. If the output exceeds the terminal height, it uses the pager defined in the $PAGER environment variable (usually less).
5. If the output fits within the terminal, it simply uses cat to display it.

To ensure the pager behaves correctly, you can set the following options in your .zshrc:

export LESS="-FXR"

This configures less to:

• Exit if the entire file fits on one screen (-F)
• Not clear the screen when exiting (-X)
• Display ANSI colors (-R)

By using this approach, you can automatically page output that exceeds the screen height while still displaying shorter output directly[1][2]. Remember to restart your Zsh session or source your .zshrc file after making these changes.

Citations: [1] https://stackoverflow.com/questions/15453394/would-it-be-possible-to-automatically-page-the-output-in-zsh/15488779 [2] https://www.reddit.com/r/bash/comments/jbcp5x/how_to_automatically_display_the_output_in_a/ [3] https://github.com/ohmyzsh/ohmyzsh/issues/3016 [4] https://github.com/sharkdp/bat/issues/749