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Comment by SwellJoe | Hacker News Reader

I'm oddly excited about command line tools lately. I've recently been porting all of our shell scripts to have color text output and Unicode status indicators (like a green checkmark for "OK" or red X for failure), when the terminal supports it (which, these days, is almost always). It just gives things a really polished feel that CLI tools don't always have.

I've used tools like dialog, in the past, but I've never really been a big fan; they seem like the worst of both worlds. It has the low-information density and high interaction requirements of a GUI, without actually looking really cool in the way a GUI can.

That's my long-winded way of saying, I also really like the way this looks, and I'm totally stealing some of the visual ideas here for my own tools.

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As of late i find myself thinking that the big DEs have been a massive distraction from what made _nix so potent. While Windows and Mac had largely tried to hide or distance themselves from the CLI in favor of the GUI, the way X11 is implemented allows CLI programs to use GUI for enhancements rather than replacements.

Blending CLI and GUI is not unique to X11; at least since .net was released on Windows this has been very easy, and it's not even that hard if you want to do this from the Win32 API.

There are also a few windows "command line" applications when invoked with bad parameters will show MsgBox or Dialog boxes instead of writing errors to the console, which is super irritating when dealing with older versions of those tools in scripts.

That said, the bog standard windows command line environment is so awful that it makes doing anything useful with this blended UI less than ideal :/

Yeah, from time to time I think that too when I browse /r/unixporn and see all the tiling window manager screens.

How is that so?

https://feh.finalrewind.org/

That is a image viewer that can be operated from the command line but that then produce a GUI window (or windows) that can be manipulated by mouse and keyboard.

It has also various options for displaying image properties in the terminal.

Meaning that it could be leveraged along with existing _nix CLI tools to fine images in a large directory (or even directory tree) and then display the result, all by piping commands together.

> I've recently been porting all of our shell scripts to have color text output and Unicode status indicators

I kinda have a similar intent of revamping user UI and user interaction of my personal scripts so I would appreciate some insights. Do you have any specific tips, helper functions or code snippets you can point me to? Do you just copy, paste and modify code snippets around when needed or have a clearly defined and reusable functions for printing, listing, displaying, prompting things etc.?

I just published the colorized logging library I am using (it's a rewrite of log4bash to support POSIX shells): https://github.com/swelljoe/slog/

I also have a few other functions I'll be wrapping up into a utility function library, once I make them all work nicely across all of the shells I'd like to support.

I'm mostly working from functions I wrote years ago and haven't touched in the interim (except to make them work with POSIX/dash, when Ubuntu switched /bin/sh from bash for 6.06).

That's great, thanks! I'm keeping an eye on other functions, too.

Just pushed out an asynchronous (cooperative, it requires the child process to touch a file to let the spinner know when to stop) Unicode and colorized progress spinner: https://github.com/swelljoe/spinner

I wouldn't call this one production ready yet. It needs to be in a function and needs to get its variables scoped and such. But, I was curious to see if a POSIX shell script could be coaxed into doing those super fun spinner designs with goofy shit like happy faces or peace signs or the like. And, it turns out you can. Long code points don't work, anywhere that I tried, yet...so my dream of a clock face with a moving hand is not yet possible. But, some day, it'll happen.

Curious if you have tried nurses at all and what you thought? Also, any useful resources for colorizing etc? I'm the sysadmin who writes the bland scripts...

I'm using tput from the ncurses package for setting colors in a terminal-aware way. You can do it with raw escape codes and most examples show it that way, but you can end up with different colors or non-functional colors on some operating systems (older macOS, among others). Using tput should smooth that out, assuming the terminal is reporting its capabilities and behavior correctly in termcap (as I understand it).

For example, I use the following to setup colors for printing log output to the display:

    readonly LOG_DEFAULT_COLOR=$(tput sgr0) # Clear colors
    readonly LOG_ERROR_COLOR=$(tput setaf 1) # Red
    readonly LOG_INFO_COLOR=$(tput sgr 0) # White
    readonly LOG_SUCCESS_COLOR=$(tput setaf 2) # Green
    readonly LOG_WARN_COLOR=$(tput setaf 3) # Yellow
    readonly LOG_DEBUG_COLOR=$(tput setaf 4) # Blue

Note that the colors are somewhat arbitrary based on the palette your terminal is using. Most palettes I've seen are kinda close to right, though green often looks olive/yellowish, and others are really washed out, in the current crop of popular palettes (like Solarized). But, it does provide color. I linked the logging library I've been using in another comment, which includes POSIX-compatible examples of using colors like this (tested on recent-ish dash, bash, zsh, and ksh).

As soon as I figure out how to reliably detect Unicode in a terminal in a POSIX compatible script, I'll publish some other utility functions that use Unicode.

The resources are pretty spread out. The tput manpage is utterly opaque, to me, as it covers a bunch of stuff that isn't relevant to "make it pretty" scripting. Mostly I've just been googling a lot. Unfortunately, the vast majority of examples on the web are for bash (also bash is easier to google for), so I'm having to trial-and-error my way to a POSIX compatible implementation.

I don't know of any way to use sh directly with ncurses itself, though there are programs like whiptail and dialog that'll harness some ncurses power for your scripts. I guess they're OK, but as I mentioned in another comment, I find dialog TUIs to be clunky. I don't want a windowing style GUI that happens to work in the CLI; I want a CLI that is traditional "run a command, get some output", but the "output" part just looks nicer, and is maybe animated in some way if it makes sense (a spinner or progress bar, e.g.).

"Curious if you have tried nurses at all and what you thought? "

Did you mean to say ncurses ? Or is there some new "nurses" thing that I don't know about ?

Oops, too late to edit now though.

>"I've recently been porting all of our shell scripts to have color text output and Unicode status indicators"

I am curious what is the upside of unicode vs plain ascii in this context?

Just for fun. It makes me smile when I see stuff like that, so I'm gonna try to make my stuff more fun. My thinking is that as long as it falls back to something safe, it isn't hurting anyone.

Probably just access to more symbols as a substitute for proper iconography.

I see, makes sense. Thanks.

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