Revision as of 11:46, 12 May 2010

As a commandline junkie, my prompt is important. It is a key element to my interface.

It needs to be both informative and terse (I can't stand 2line prompts for eg)

I have used ZSH as my shell of preference since roughly the turn of the century. (previously: bash). Part of the incentive to switch was the prompt interface features found in zsh that were not in bash at the time. (my memory has right-aligned-prompt as notable, but I'm sure there were more reasons than just that ;)

The prompt I use dates it's heritage back to an old dos (specifically: 4DOS) prompt that I setup in... 1994, for a guess.

Features

currently implemented

prompt action

• last job exit status (invisible when zero)
• host:path in network friendly (ish) format
• path shortening to last three components, plus subtle visual indication when this occurs (deliminating colon changes from host colour to directory colour)
  • this shortening balances path context needs with space limitations. and is why the preceeding 'network friendly' format is "ish" :)
• path colourisation to indicate whether $PWD is RW or not (not usually means RO, but may also mean 'directory does not exist')
• count of background jobs (invisible if zero)
• ^ and $ reminder mnemonic for regex start/end line matching (I have a dyslexia about this!)
• live time and load average (load gets dynamic colourisation also, but is invisible below threshold (set to 0.3 for me)
  • for values of "live" that = "20 second refresh"
  • this refresh ensures that an abandoned prompt will keep-alive a remote shell over dodgy NAT :)
• current tty

under consideration / TODO

these have been suggested, but not yet implemented. Or maybe I wont implement them - but I haven't decided yet

• per-host auto-colourisation
  • http://screwtape.jottit.com/per-host_prompt_colouring
• vcs_info (I would probably replace tty info with this, with a colourisation to help the glancing eye notice)
  • http://ft.bewatermyfriend.org/comp/zsh/functions/prompt_ft_setup.html
    • example of vcs_info
  • note comment from screwtape: http://identi.ca/conversation/31704527#notice-31817077
• active group when not default
• UID=0 indication (technically simple, but I prefer a more obvious change for my root user prompt. I don't use it, but it wont hurt... right? :)
• username - this is not currently included for space reasons. I know my username because I'm seeing *my prompt*. I tend to leave the default prompt set for other users on the system (including root)

ignored / NOT be implemented

note: some of these were clearly suggested in jest :)

• http://www.facebook.com/#!/nemothorx?v=wall&story_fbid=121814377837169&ref=mf
  • Free disk, highest mem and CPU process, length of current prompt! -- Norgus (facebook)
  • current Dow, weather and TV listings -- Julian (facebook)

Configuration

here is my prompt config

http://wiki.thorx.net/~nemo/s/zsh_ps1.txt

warning: it's full of comments and code cruft, both from old revisions, and also future plans.