6 ms·

Useful Shell Prompt (2020)

56 points by webmaven 5y ago

branon 5y ago
Can the red arrow be done in Bash?
- diroussel 5y ago
  Install https://starship.rs https://starship.rs it works with bash and zsh, and many others shells. And you get the red arrow for failed commands out of the box. No extra config required.
Canada 5y ago
Wow, that's the only useful fancy prompt I've ever seen over \w\$
kazinator 5y ago
Here is a useful prompt: PS1='$?:[$(date +%m%d:%H%M%S)]:\h:\w\$ ' you have - termination status of the last command - date and time the prompt was last redrawn in [MMDD:HHMMSS] form. - host, working dir, prompt character #-root $-user
- deleted 5y ago
  [deleted]
wodenokoto 5y ago
I've been using pure theme for a few years and absolutely love it. It shows me everything I need, but doesn't feel cluttered. It uses 2 lines, which is actually really nice. It gives space to show where you are and git status/branch, while still allowing you to write long commands. https://github.com/sindresorhus/pure https://github.com/sindresorhus/pure
- mekster 5y ago
  I don't get why everyone wants git status on every prompt. It feels more of a distraction than necessity just to make it look prettier for screenshot purposes. Most of the time I'm within a repo directory, I don't care in which branch or state it's in as I have other apps to take care of that and there are better info to be had like cwd, who you're, host name, exit code, time and time last command took for a prompt.
  - petepete 5y ago
    I admit that having the branch name always there is overkill, but having it display your rebase status or flag when there are uncommitted changes is genuinely useful.
  - wodenokoto 5y ago
    I use it all the time. When working in GCP, I could really have used a prompt that told me current gcp project. But sure, if you are not using hit in your shell, then you don’t need fit in your shell.
  - BiteCode_dev 5y ago
    If you multitask between several projects, it becomes very useful very fast.
    - diroussel 5y ago
      Also it’s useful to see what branch you were on when you ran a particular command, as you scroll up through the commands and outputs you ran previously.
relyks 5y ago
fish already does this in most of the included prompt themes :)
deathanatos 5y ago
I used to use a colored indicator for the exit status, but a while ago I switched to a multiline prompt: (last command returned 1.) » Or, if the previous command terminates due to a signal: (last command got signal SIGTERM.) » Color doesn't survive c/p in practically any medium, and the exit status is useful when showing things to co-workers. The bigger hint also highlights when a command unexpectedly errors (e.g., while emitting text to the effect of "Success!") and the opposite case, where a command appears to fail and exits with success anyways.
- yjftsjthsd-h 5y ago
  Oh, that's very nice. By any chance have you posted your dotfiles somewhere so that I can steal it?
  - deathanatos 5y ago
    https://github.com/thanatos/dotfiles/blob/master/shell/zsh/prompt-alpha#L108-L171 https://github.com/thanatos/dotfiles/blob/master/shell/zsh/p... I've tried to highlight roughly the relevant bits. The basics of it is that we lazy-load an associative array between exit statuses that are signals and their prettified names. (Which we more or less build by querying Python, to get at what's, essentially, defined in signal.h.) Once we have that assoc. array, when we get a non-zero exit, we see if it's in the array. If it is, look up the pretty name, print message. If not, just print message with raw exit status. Red & bold so it shows up. (Should probably also use bright red, too. But my work laptop is macOS, & so it's iTerm2, and iTerm2 interprets "bold" to mean "bright & bold".) I also use zsh, which is able to be considerably more expressive in what it can accomplish in a PS1 than bash can. Note that the syntax, ${+VAR} which appears in there is zsh-specific. It can be done in bash, but it isn't as neat. I don't recall if bash has associative arrays or just arrays, too…
- tom_ 5y ago
  I've been doing this a long time in 4NT. PROMPT=[$r][ $P ][ $t ]$_$g Appearance is along these lines: [0][ C:\bin\4nt ][ 15:30:07 ] > Super useful. It's good to get advance warning of strange exit codes when trying things out interactively with a view to using them in some automated process. The exit code also shows the exception type if the process terminates due to an exception - alway handy to know. I also like always having the same amount of space for the command, visually, regardless of the working folder.
cocoa19 5y ago
If you love this, you should try ohmyzsh. The default prompt with the status arrow and directory are awesome. You can also extend ZSH functionality with plugins. I can't live without git and timer plugins anymore.
- bloopernova 5y ago
  https://github.com/romkatv/powerlevel10k https://github.com/romkatv/powerlevel10k :)
- rubyist5eva 5y ago
  I personally prefer prezto to omz because omz feels noticeably sluggish on my machines, whereas you can use prezto with powerlevel10k (built-in, just need to switch the theme in the config) and it’s lightning fast. Can’t use anything else after getting used to how fast it is.
chasil 5y ago
Debian dash can be compiled with editing modes for vi and emacs. There is great love from many for more capable shells, but the flaws of these are visible to all; "man bash" plainly states that it's "too big and too slow." Minimal dash compiles to under 80k for i686, and Arch Linux asserts it to be 4x faster than bash. It is with some regret that we did not adopt a shell syntax that could be cleanly LR-parsed with yacc and lex, but that was the fault of the founders. Bill Joy has admitted his own flaws in the C shell, and Brian Kernigan should have torn that code apart, replacing it with awk syntax upon a shell. In a parallel world, it would have been a much more capable shell. As things stand, we must struggle with the Algol of our forbearers, that requires an extremely advanced parser, and to make due with what is permitted to us. https://m.youtube.com/watch?v=fiJR4_059HA https://m.youtube.com/watch?v=fiJR4_059HA
- chasil 5y ago
  The author of the musl C library has this to say about the POSIX shell: "I am a strong believer that Bourne-derived languages are extremely bad, on the same order of badness as Perl, for programming, and consider programming sh for any purpose other than as a super-portable, lowest-common-denominator platform for build or bootstrap scripts and the like, as an extremely misguided endeavor." https://www.etalabs.net/sh_tricks.html https://www.etalabs.net/sh_tricks.html
  - mro_name 5y ago
    > super-portable what else may come in mind to use?
  - opk 5y ago
    The basic unit on which shell scripts build is external commands. If what you want to do is to tie a few together, it is by far the best tool. For the type of programming problem where you need data structures it is indeed awful. But things like Python are really quite poor when it comes to executing external commands. You either need a dozen lines for each external command or things are done in a crap way with commands running synchronously when they don't need to be. With many real languages, people use a `system()` function that is running sh every time along with evaluation because the alternative is fork/exec/wait etc. Many of those sh tricks you link to are better even in the common ksh/bash/zsh subset than in pure POSIX.
gorgoiler 5y ago
I’ve started putting more things in tmux status, down and to the right. Repo/cwd, branch, and commits beyond master are pretty handy things to see. They change a lot depending on which window I’m in. It would be cool in tmux to have a shortcut to a quick popup showing more git info (status, log origin.., which of the patches have pull requests.) You could do that stuff with a shell command or a vim plugin, but tmux is the common thread, so adding it there seems a better place for it. Kind of like a sticky window in a tiling wm (mod space in i3) but in the terminal.
rgoulter 5y ago
The starship prompt is astoundingly good value-for-effort. https://starship.rs/ https://starship.rs/ It's very feature-rich, showing suitable context for a variety of tools, and can be customised if the defaults don't provide the information you're after.
- wodenokoto 5y ago
  The website says it’s feature rich. Do they have a list of features? Is there any reason why a prompt is written in rust?
  - rgoulter 5y ago
    I'd take a look at the headers under the configuration options. (e.g. AWS, Git, Python, Status). https://starship.rs/config/ https://starship.rs/config/ > Is there any reason why a prompt is written in rust? The prompt program supports a bunch of different shells. I imagine that's going to be easier to maintain in Rust than in bash.
  - 3836293648 5y ago
    Shell is kinda awful to write, so people started using python, which is too slow for this (just the startup times...), so they moved to rust
  - avgcorrection 5y ago
    The question “Why isn’t this written in Rust” is ridiculous and a distraction but “why is […]” is even moreso.
- diroussel 5y ago
  Starship.rs is great. It has the red prompt feature mentioned in TFA by default. And it’s fast. And means I can easily have the same prompt in bash and zsh, on macos and Linux.
mkdirp 5y ago
If you're running zsh, I suggest using powerlevel10k[0]. It is stupid fast, and extremely customisable. [0] https://github.com/romkatv/powerlevel10k https://github.com/romkatv/powerlevel10k
- wantguns 5y ago
- bloopernova 5y ago
  For p10k users, adding extra info to your prompt is really easy. Here's my epoch-seconds display: function prompt_epoch() { MYEPOCH=$(/bin/date +%s | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta') p10k segment -f 66 -t ${MYEPOCH} } It looks like this in action: https://i.imgur.com/0IT5zXi.png https://i.imgur.com/0IT5zXi.png
  - tomtom1337 5y ago
    Your imgur link isn't working for me. I'm getting an "oops we can't find the image".
    - bloopernova 5y ago
      Does this work? https://imgur.com/0IT5zXi https://imgur.com/0IT5zXi
  - JNRowe 5y ago
    In the spirit of p10k speed, you can perform that task without forks: $ zmodload -F zsh/datetime p:EPOCHSECONDS $ printf "%'d" $EPOCHSECONDS 1,648,943,504
    - bloopernova 5y ago
      Nice, thank you!
    - bloopernova 5y ago
atemerev 5y ago
So, basically, what fish gives out of the box :)
KSPAtlas 5y ago
I set up a status based prompt too - but in bash instead
novocantico 5y ago
Related to this, something I did 10 years ago and started seeing more often (especially in git-bash!) is to have * a newline before your current prompt * a newline after all your context and right before your "$ " This helped me tremendously with scanning terminal output for years. More default $PS1's should do this.
simonsaysso 5y ago
I'm a huge, huge fan of writing your own prompt. I've had too many people not actually understand what was being displayed to them by their latest and prettiest version of their prompt and have to walk them through it. The folks posting here are unlikely to be in this camp, but I've had people with their full working directory in the prompt running `pwd`. If you're not going to use the information from the prompt, don't include it. A big problem I had at a former employer was that `git status` would take 2+ seconds to return (for various reasons) and the default oh-my-zsh prompt would parse the results of `git status` to display the repository. People thought it was normal to wait more than half a second to get a prompt back! I lost trust in 3rd party prompts from that experience, and while I have sunk at least a few hours into my own prompt, I know exactly how it works, what calls it's making, and where things go wrong (when they do).

56 points by webmaven 5y ago

branon 5y ago

Can the red arrow be done in Bash?

diroussel 5y ago
Install https://starship.rs https://starship.rs it works with bash and zsh, and many others shells. And you get the red arrow for failed commands out of the box. No extra config required.

Canada 5y ago

Wow, that's the only useful fancy prompt I've ever seen over \w\$

kazinator 5y ago

Here is a useful prompt: PS1='$?:[$(date +%m%d:%H%M%S)]:\h:\w\$ ' you have - termination status of the last command - date and time the prompt was last redrawn in [MMDD:HHMMSS] form. - host, working dir, prompt character #-root $-user

deleted 5y ago
[deleted]

wodenokoto 5y ago

I've been using pure theme for a few years and absolutely love it. It shows me everything I need, but doesn't feel cluttered. It uses 2 lines, which is actually really nice. It gives space to show where you are and git status/branch, while still allowing you to write long commands. https://github.com/sindresorhus/pure https://github.com/sindresorhus/pure

mekster 5y ago
I don't get why everyone wants git status on every prompt. It feels more of a distraction than necessity just to make it look prettier for screenshot purposes. Most of the time I'm within a repo directory, I don't care in which branch or state it's in as I have other apps to take care of that and there are better info to be had like cwd, who you're, host name, exit code, time and time last command took for a prompt.
- petepete 5y ago
  I admit that having the branch name always there is overkill, but having it display your rebase status or flag when there are uncommitted changes is genuinely useful.
- wodenokoto 5y ago
  I use it all the time. When working in GCP, I could really have used a prompt that told me current gcp project. But sure, if you are not using hit in your shell, then you don’t need fit in your shell.
- BiteCode_dev 5y ago
  If you multitask between several projects, it becomes very useful very fast.
  - diroussel 5y ago
    Also it’s useful to see what branch you were on when you ran a particular command, as you scroll up through the commands and outputs you ran previously.

relyks 5y ago

fish already does this in most of the included prompt themes :)

deathanatos 5y ago

I used to use a colored indicator for the exit status, but a while ago I switched to a multiline prompt: (last command returned 1.) » Or, if the previous command terminates due to a signal: (last command got signal SIGTERM.) » Color doesn't survive c/p in practically any medium, and the exit status is useful when showing things to co-workers. The bigger hint also highlights when a command unexpectedly errors (e.g., while emitting text to the effect of "Success!") and the opposite case, where a command appears to fail and exits with success anyways.

yjftsjthsd-h 5y ago
Oh, that's very nice. By any chance have you posted your dotfiles somewhere so that I can steal it?
- deathanatos 5y ago
  https://github.com/thanatos/dotfiles/blob/master/shell/zsh/prompt-alpha#L108-L171 https://github.com/thanatos/dotfiles/blob/master/shell/zsh/p... I've tried to highlight roughly the relevant bits. The basics of it is that we lazy-load an associative array between exit statuses that are signals and their prettified names. (Which we more or less build by querying Python, to get at what's, essentially, defined in signal.h.) Once we have that assoc. array, when we get a non-zero exit, we see if it's in the array. If it is, look up the pretty name, print message. If not, just print message with raw exit status. Red & bold so it shows up. (Should probably also use bright red, too. But my work laptop is macOS, & so it's iTerm2, and iTerm2 interprets "bold" to mean "bright & bold".) I also use zsh, which is able to be considerably more expressive in what it can accomplish in a PS1 than bash can. Note that the syntax, ${+VAR} which appears in there is zsh-specific. It can be done in bash, but it isn't as neat. I don't recall if bash has associative arrays or just arrays, too…
tom_ 5y ago
I've been doing this a long time in 4NT. PROMPT=[$r][ $P ][ $t ]$_$g Appearance is along these lines: [0][ C:\bin\4nt ][ 15:30:07 ] > Super useful. It's good to get advance warning of strange exit codes when trying things out interactively with a view to using them in some automated process. The exit code also shows the exception type if the process terminates due to an exception - alway handy to know. I also like always having the same amount of space for the command, visually, regardless of the working folder.

cocoa19 5y ago

If you love this, you should try ohmyzsh. The default prompt with the status arrow and directory are awesome. You can also extend ZSH functionality with plugins. I can't live without git and timer plugins anymore.

bloopernova 5y ago
https://github.com/romkatv/powerlevel10k https://github.com/romkatv/powerlevel10k :)
rubyist5eva 5y ago
I personally prefer prezto to omz because omz feels noticeably sluggish on my machines, whereas you can use prezto with powerlevel10k (built-in, just need to switch the theme in the config) and it’s lightning fast. Can’t use anything else after getting used to how fast it is.

chasil 5y ago

Debian dash can be compiled with editing modes for vi and emacs. There is great love from many for more capable shells, but the flaws of these are visible to all; "man bash" plainly states that it's "too big and too slow." Minimal dash compiles to under 80k for i686, and Arch Linux asserts it to be 4x faster than bash. It is with some regret that we did not adopt a shell syntax that could be cleanly LR-parsed with yacc and lex, but that was the fault of the founders. Bill Joy has admitted his own flaws in the C shell, and Brian Kernigan should have torn that code apart, replacing it with awk syntax upon a shell. In a parallel world, it would have been a much more capable shell. As things stand, we must struggle with the Algol of our forbearers, that requires an extremely advanced parser, and to make due with what is permitted to us. https://m.youtube.com/watch?v=fiJR4_059HA https://m.youtube.com/watch?v=fiJR4_059HA

chasil 5y ago
The author of the musl C library has this to say about the POSIX shell: "I am a strong believer that Bourne-derived languages are extremely bad, on the same order of badness as Perl, for programming, and consider programming sh for any purpose other than as a super-portable, lowest-common-denominator platform for build or bootstrap scripts and the like, as an extremely misguided endeavor." https://www.etalabs.net/sh_tricks.html https://www.etalabs.net/sh_tricks.html
- mro_name 5y ago
  > super-portable what else may come in mind to use?
- opk 5y ago
  The basic unit on which shell scripts build is external commands. If what you want to do is to tie a few together, it is by far the best tool. For the type of programming problem where you need data structures it is indeed awful. But things like Python are really quite poor when it comes to executing external commands. You either need a dozen lines for each external command or things are done in a crap way with commands running synchronously when they don't need to be. With many real languages, people use a `system()` function that is running sh every time along with evaluation because the alternative is fork/exec/wait etc. Many of those sh tricks you link to are better even in the common ksh/bash/zsh subset than in pure POSIX.

gorgoiler 5y ago

I’ve started putting more things in tmux status, down and to the right. Repo/cwd, branch, and commits beyond master are pretty handy things to see. They change a lot depending on which window I’m in. It would be cool in tmux to have a shortcut to a quick popup showing more git info (status, log origin.., which of the patches have pull requests.) You could do that stuff with a shell command or a vim plugin, but tmux is the common thread, so adding it there seems a better place for it. Kind of like a sticky window in a tiling wm (mod space in i3) but in the terminal.

rgoulter 5y ago

The starship prompt is astoundingly good value-for-effort. https://starship.rs/ https://starship.rs/ It's very feature-rich, showing suitable context for a variety of tools, and can be customised if the defaults don't provide the information you're after.

wodenokoto 5y ago
The website says it’s feature rich. Do they have a list of features? Is there any reason why a prompt is written in rust?
- rgoulter 5y ago
  I'd take a look at the headers under the configuration options. (e.g. AWS, Git, Python, Status). https://starship.rs/config/ https://starship.rs/config/ > Is there any reason why a prompt is written in rust? The prompt program supports a bunch of different shells. I imagine that's going to be easier to maintain in Rust than in bash.
- 3836293648 5y ago
  Shell is kinda awful to write, so people started using python, which is too slow for this (just the startup times...), so they moved to rust
- avgcorrection 5y ago
  The question “Why isn’t this written in Rust” is ridiculous and a distraction but “why is […]” is even moreso.
diroussel 5y ago
Starship.rs is great. It has the red prompt feature mentioned in TFA by default. And it’s fast. And means I can easily have the same prompt in bash and zsh, on macos and Linux.

mkdirp 5y ago

If you're running zsh, I suggest using powerlevel10k[0]. It is stupid fast, and extremely customisable. [0] https://github.com/romkatv/powerlevel10k https://github.com/romkatv/powerlevel10k

wantguns 5y ago
bloopernova 5y ago
For p10k users, adding extra info to your prompt is really easy. Here's my epoch-seconds display: function prompt_epoch() { MYEPOCH=$(/bin/date +%s | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta') p10k segment -f 66 -t ${MYEPOCH} } It looks like this in action: https://i.imgur.com/0IT5zXi.png https://i.imgur.com/0IT5zXi.png
- tomtom1337 5y ago
  Your imgur link isn't working for me. I'm getting an "oops we can't find the image".
  - bloopernova 5y ago
    Does this work? https://imgur.com/0IT5zXi https://imgur.com/0IT5zXi
- JNRowe 5y ago
  In the spirit of p10k speed, you can perform that task without forks: $ zmodload -F zsh/datetime p:EPOCHSECONDS $ printf "%'d" $EPOCHSECONDS 1,648,943,504
  - bloopernova 5y ago
    Nice, thank you!
  - bloopernova 5y ago

atemerev 5y ago

So, basically, what fish gives out of the box :)

KSPAtlas 5y ago

I set up a status based prompt too - but in bash instead

novocantico 5y ago

Related to this, something I did 10 years ago and started seeing more often (especially in git-bash!) is to have * a newline before your current prompt * a newline after all your context and right before your "$ " This helped me tremendously with scanning terminal output for years. More default $PS1's should do this.

simonsaysso 5y ago

I'm a huge, huge fan of writing your own prompt. I've had too many people not actually understand what was being displayed to them by their latest and prettiest version of their prompt and have to walk them through it. The folks posting here are unlikely to be in this camp, but I've had people with their full working directory in the prompt running `pwd`. If you're not going to use the information from the prompt, don't include it. A big problem I had at a former employer was that `git status` would take 2+ seconds to return (for various reasons) and the default oh-my-zsh prompt would parse the results of `git status` to display the repository. People thought it was normal to wait more than half a second to get a prompt back! I lost trust in 3rd party prompts from that experience, and while I have sunk at least a few hours into my own prompt, I know exactly how it works, what calls it's making, and where things go wrong (when they do).