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Comment by siraben | Hacker News Reader

Awk is awesome! Glad that they are looking to modernize the book. It wasn't really necessary, all the code examples in the original edition of the book still run just fine, although some are somewhat dated, like printing ASCII bar graphs. They also had examples of writing VMs, parsers and interpreters in the book, which run on modern implementations.[0]

The language has some quirks. To declare temporary variables, it's common practice to add extra arguments to functions that won't be used. And traversal of associative arrays is implementation-dependent. I'm not sure what the situation is regarding locale and UTF-8 support.

EDIT: Looks like Brian Kernighan added Unicode support last year.[1]

[0] https://github.com/siraben/awk-vm/blob/master/vm.awk

[1] https://github.com/onetrueawk/awk/commit/9ebe940cf3c652b0e37...

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What would you suggest as an alternative to printing ASCII bar graphs? I do that all the time. Takes 20 seconds and often makes distributions, modalities, and patterns over time obvious right away.

`sparklines`[1] is good for an overall low-res view. `termgraph`[2] is sometimes better for a higher-res, more capable view (but can be finicky about the data.)

[1] https://github.com/deeplook/sparklines

[2] https://github.com/mkaz/termgraph

But both require depending on a third party library -- hardly something on a whim if ASCII bar charts do the job?

gnuplot is an alternative that is available on almost as many systems as awk, and can do the job as well

edit: this prompted me to write up a little note showing how: https://notes.billmill.org/visualization/graphs/gnuplot/A_ba...

If you do this sort of thing more than once ever, look at the feedgnuplot tool (http://github.com/dkogan/feedgnuplot). It'll make your life easier

Neat! Once you're installing something to do terminal plots though, https://github.com/red-data-tools/YouPlot looks the nicest I've seen.

(The nice feature of feedgnuplot of course is that you can _also_ render the plots to images, which youplot can't)

> which youplot can't

But you could feed them through `textimg`[1] to generate PNGs.

[1] https://github.com/jiro4989/textimg

lol, I love it

Sure but, e.g., sparklines can show me the shape of my 60 numbers[1] more effectively on a single line of 60 characters[2] than an ASCII bar chart which would be 60 lines (without binning).

[1] 27623 14272 22218 21267 19037 989 27116 32405 23261 27104 7793 9432 7776 28832 13521 10783 29261 32193 30367 20358 22611 2023 19607 9844 3516 6510 16533 8378 22986 17043 14628 13392 22799 23847 29212 23690 17779 17059 28211 26180 32061 22740 7911 12018 4508 9801 9578 15350 9554 15517 11112 405 22054 2743 26609 7843 713 10975 2830 1126

[2] http://rjp-hosted-files.s3.amazonaws.com/sparkline-demo.png

Is there a particular benefit in writing a VM in AWK, placed in a big BEGIN block? Very similar code can be written in Perl or Python. Isn't the strength of AWK in its line-matching capability, being able to pattern-match a line against a block of code?

> Is there a particular benefit in writing a VM in AWK

Not really. Later on the book just ran out of line-matching examples to go through and started doing regular programming instead :P. When I actually write AWK code I rely on line-matching and using a variable to handle state.

At the time, awk was the only scripting language (other than shell) generally available on Unix systems. Perl, Tcl, Python didn't exist yet. So awk was often used for general-purpose programming.

I love telling about that example to my programming language friends.

> Hey you should read the AWK book, it even says how to write a VM!

> Why would I ever want to use AWK for that?

> Well, the input is a text file with one space-delimited instruction per line.

> Hmm... You have a point.

AWK runs everywhere. Perl and Python do not.

Busybox has their own independent AWK implementation.

https://busybox.net/ https://frippery.org/busybox/

Also see the first edition of the AWK manual online here:

https://archive.org/details/pdfy-MgN0H1joIoDVoIC7

I'm sorry, where does Awk run but Perl and Python don't?

If we're counting minimalist implementations, there's micropython that even runs on microcontrollers that cost a less than 2 dollars.

Small, embedded, busybox systems - per the parent comment.

Like I said, MicroPython can run even on microcontrollers.

I think parent may be more implying “living off the land” situations. Awk is ubiquitous, and part of the POSIX standard. Micro Python, not so much.

I’m a big fan of Forth, but it’s not available everywhere. One has to adapt.

The POSIX standard mandates awk.

It does not mandate Perl or Python.

<https://pubs.opengroup.org/onlinepubs/9699919799/utilities/a...>

<https://pubs.opengroup.org/onlinepubs/9699919799/utilities/c...>

There are many systems which lack Perl or Python, but include awk.

You might be carrying an Android device at the moment --- if you drop to its default userland, that provides a bunch of utilities, including awk, via Busybox. But not, so far as I'm aware, either Perl or Python.

(You can of course install Termux which will then give you both Perl and Python, along with Node.js, ruby, and a whole slew of other scripting and compiled languages. But so long as we're considering stock installs, it's sed and awk.)

On wm's, why not a Z-machine? It's ideal for this.

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