Dt: Duck tape for your Unix pipes
dt.plumbing
dt.plumbing
> She is often misattributed as the inventor of duct tape. However, numerous variations of adhesive cotton duck tape had existed for decades, nor did she invent the specific formulation of the popularized duct tape.
Duct tape has kinda become a general term for all cloth-based tapes though, so you can indeed find duct tape not intended for ducts, but the fact the name was originally “duck tape” has nothing to do with that.
Gaffer Duck
Donald Duck
These toons stick together
[0] https://tapeuniversity.com/products/foil-tapes/ul181ap-ul181...
Even your own source on a separate page [3] says:
> After the war, duct tape became popular with the general public. One popular use was holding together ventilation ducts. Ironically, while this is a use that duct tape does not normally have today, the name stuck and is used to this day.
So I am now confused.
[0] https://www.chicagotribune.com/redeye/redeye-is-it-duck-or-d... [1] https://en.m.wiktionary.org/wiki/duct_tape [2] http://www.todayifoundout.com/index.php/2010/02/duct-tape-wa... [3] https://tapeuniversity.com/industry/building-construction/du...
The part I quoted says that duck tape is made of cloth and therefore is not duct tape.
I think people get confused because there is a brand of duct tape named Duck Tape. But even the Duck Tape packaging calls it a "duct tape".
I am sorry, but you are wrong. The term duct tape is specifically referring to “Duct tape: cloth- or scrim-backed pressure-sensitive tape, often coated with polyethylene.” We don’t even need to argue if it is good for use in ducts, it is not, I agree. However, that isn’t what we are discussing here. From Wikipedia: “The ultimate wide-scale adoption of duck tape, today generally referred to as duct tape, came from Vesta Stoudt. Stoudt was worried that problems with ammunition box seals could cost soldiers precious time in battle, so she wrote to President Franklin D. Roosevelt in 1943 with the idea to seal the boxes with a fabric tape which she had tested. … [Johnson & Johnson’s] new unnamed product was made of thin cotton duck coated in waterproof polyethylene (plastic) with a layer of rubber-based gray adhesive (branded as "Polycoat") bonded to one side. It was easy to apply and remove, and was soon adapted to repair military equipment quickly, including vehicles and weapons. This tape, colored in army-standard matte olive drab, was widely used by the soldiers. After the war, the duck tape product was sold in hardware stores for household repairs. The Melvin A. Anderson Company of Cleveland, Ohio, acquired the rights to the tape in 1950. It was commonly used in construction to wrap air ducts. Following this application, the name "duct tape" came into use in the 1950s, along with tape products that were colored silvery gray like tin ductwork. Specialized heat- and cold-resistant tapes were developed for heating and air-conditioning ducts.”
> The part I quoted says that duck tape is made of cloth and therefore is not duct tape.
The part you quoted doesn’t say that at all. The part you quoted says “She is often misattributed as the inventor of duct tape. However, numerous variations of adhesive cotton duck tape had existed for decades, nor did she invent the specific formulation of the popularized duct tape.” Did you quote the wrong thing? It’s simply saying that the duct tape Vesta Stoud developed was not the final product we know today, nor was she the first to come up with the idea.
> I think people get confused because there is a brand of duct tape named Duck Tape. But even the Duck Tape packaging calls it a "duct tape”
I honestly can’t keep track anymore.
I had always assumed it was the other way round, and some people simply don't know what a duct is so they substitute a similar-sounding, more common word.
Courts do not accept all lawsuits.
And never mind the dog named dog (a long time ago, some IEEE journal had a great cartoon where someone painted "house" on their house, "car" on their car, ... you get it. The cartoon illustrated an article about good and bad names for systems.
i think the best way of naming a company is to make it something that is said hundreds of times by people every day
"an apple a day" etc... wonder if I can name my comapny "the The company"
or "the corporation of Is" haha
And then so many people post “facts” about a clearly fuzzy issue and proceed to argue about who’s “right”. I’m getting real blegg/rube vibes from the whole argument here.
This is how I always understood the situation, and then I've recently discovered the issue is further "muddied" by a brand name/trademark "Duck Tape" also, so that's fun...
https://www.lowes.com/pd/3M-2-5-in-W-x-150-ft-L-HVAC-Tape/40...
But I grew up calling it "gaffer's tape", because it was popularly used by gaffers on film and TV sets.
Even in that article, the two definitions are very, very close to being the same thing, and in the studios I was familiar with, both of the tapes the article defines would have been referred to as "gaffer's tape". They're just different varieties of gaffer's tape.
It's all just slang, though, so I'm not surprised that the definition varies from crowd to crowd.
Damn, that neuron hasn't lit up since about 1992.
Duck tape kind of sucks for most temporary applications as it leaves so much residue behind. Gaffer tape is an awesome replacement (although quite a bit pricier).
Their acceptance speech was written in Seussian rhyme. "Do not use duct tape on ducts. Do not use it: t'won't stay stuck."
Also +1 for Gaffer tape, especially for audio/video.
It's a nice waterproof alternative to oil based materials as the cotton swells when wet to seal its own seams.
FWIW I've been using *nix machines for decades, and very rarely have I had the need to use structured data between commands. Yes, it would make things cleaner or more robust in certain cases, but in practice there are common ways of handling this. E.g. most tools support outputting or inputting null-terminated lines.
The world would be a much happier place if -print0 (or whatever) was universal, but no such luck.
If programs simply input and output unstructured data, it's up to the user to (de)structure this data in any way they need. The loose coupling is a feature, not a bug.
[1]: You can see this in Nushell's issue tracker[2]. I'm not judging the amount of issues, as any healthy OSS project will have many issues, but some of these are critical bugs related to command handling and interop. I'm not blaming the Nushell team either, my hat's off to them, but just pointing out that the nature of the project will inevitably lead to a neverending stream of these types of issues.
I think you're misunderstanding how Nushell works. They don't parse outputs, or generate inputs, from/for standard Unix commands. Instead, they implement their own commands with the same names as standard commands, and generate/consume structured data by default, using the same data structures everywhere. There is only a single implementation of those data structures. That's very easy to maintain.
So running `ls` from Nushell does not shell out to the `ls` program on your system, and then try to make sense of its output. It runs a Nushell-internal command that is tailored to the kind of pipelines that Nushell is built around. They already have hundreds such commands implemented and working, and that approach absolutely does scale. Whatever issues may remain, it already works much more reliably than the default Unix tools.
Saying that unstructured text streams are a universal interface is like saying that atoms are a universal construction kit – it's technically correct, but pretty useless in practice.
But, hey, this obviously has users who prefer it, so if this works for you, that's great. Personally, I'll stick to the standard GNU and POSIX tools. I do concede that this is partly due to the robustness of this ecosystem and my familiarity with it, which is hard to abandon.
> Saying that unstructured text streams are a universal interface is like saying that atoms are a universal construction kit – it's technically correct, but pretty useless in practice.
My point is that offloading the decision of how the tools are integrated beyond raw byte streams to the user, is the most flexible and future-proof approach, with the least overhead for individual tools. Doing anything more sophisticated, while potentially easier for the user, would require maintenance of the glue layer by each tool's developer, or a central maintainer ala Nushell. This loose coupling is a good thing.
The existing tools aren't fully compatible with each other either. There are significant differences between GNU and BSD tools, for example, and yet more differences with BusyBox and others. The idea of "standard" tools is unfortunately an illusion, so not much is lost there.
But more importantly, most of the many options the traditional tools offer are related to output selection and formatting. In Nushell, those problems are solved in a unified way by piping to builtin commands that work with structured data. So instead of learning twenty different cryptic flags for `ls`, you just learn three or four postprocessing commands, and use them for `ls` and everything else.
Right, but those incompatibilities, as well as the way commands interoperate, are left to the user to resolve. No monolithic tool could realistically make that easier, unless they reimplement everything from scratch, as Nushell has done. But then you have to work with an entirely different and isolated ecosystem, and you depend on a single project to maintain all your workflows for you. Again, the ability for loosely coupled tools to work together is one of the strengths of Unix.
We clearly have a difference of opinion here, so let's agree to disagree. :)
Without ever having tried it, I know that one random day when I for whatever reason have a wish to take the output from bsd grep and send it over tcp through netcat, to be collected by zsh's built-in tcp support and fed in to gnu's grep, it will work. No piece along the way made any jerk assumptions or required any any jerk tight coupling, and the bsd and gnu tools were completely compatible.
That is more valuable and greater convenience than any other poorly concieved ideas to make it more convenient.
This all 50 years after unix pipes were invented and in an environment the inventors did not even try to predict and handle. Instead they handled infinity by not trying to predict anything. They just made useful low level tools which you assemble however you may turn out to need to, and the tools make as few as possible assumptions which will all eventually break. The hammer doesn't only work with one kind of nail.
Most output is relatively easy to parse, sometimes you need to annotate the pipe with what format to expect but that’s easy enough to do. And Murex does come with builtins that cover some of the more common coreutils use cases for instances when you want greater assurances of the quality of the data - but those are named differently to their coreutil counterparts to avoid confusion.
How would you say Murex compares to Nushell? The syntax seems vaguely similar. Are there any fundamental differences?
Murex was created before most of the alt shells existed, created to scratch a personal itch. It's only relatively recently that I've been promoting it. What I wanted to create was a shell that had typed pipes but still worked 100% with traditional POSIX abstractions. So it's still just standard POSIX pipes underneath so type information is sent out-of-band. This basically means you can have a richer set of functionality from anything that understands Murex while still falling back to plain old byte streams for anything that doesn't.
I've also taken inspiration from IDEs with regards to the interactive UX. You'll get syntax highlighting, dynamic autocompletions based from man pages (I'm shortly going to push an enhancement in that area as well), smarter hints (like tool tips), inline spell checking, and all sorts.
There's also been some focus on making the shell more robust. Such as built in unit test framework, watches (for debugging), etc.
There will still be plenty of rough edges (as is the case with all shells to be honest) but it's a vast improvement over Bash in my biased opinion. So much so that it's been my primary shell for > 5 years.
Still, you must have issues parsing all variations of output, depending on the flags passed to the source command and its version. How do you parse the output of ls or ps without knowing the column headers, delimiters, or which version of the command was ran (GNU, BSD, BusyBox, etc.)? Piping data into commands also must require a wrapper of some sort.
Not knocking on the project, it does look interesting, especially the saner scripting language. But the usefulness seems limited to the commands and workflows it supports.
The current implementation does break a little if records contain a space as part of its input (eg ‘command parameter parameter’ in ps) but I’m working on some code that would look at column alignment as well as separators etc — basically reading the output like a human might but without going to the extreme of machine learning. (I’m already doing this to parse man pages and --help output as part of automatic autocompletions so I know the theory works, I just haven’t yet applied that to more generalised command output).
Sometimes I daydream about a parallel universe in which the designers of Unix decided on record-oriented IO instead of stream-oriented IO.
If pipes were defined in terms of records as opposed to an unstructured byte stream, there'd be no need for a special character (whether newline or null) to separate records. How is in-band signalling in pipes any better than in-band signalling in telecommunications?
I would attack you with tea bags and waxed paper, if you tried to alter the timeline, and make this so.
On the other hand, I would happily sing your praises, if you invented another kind of pipe, to your specs, it sounds like a great additional.
Imagine combining the two, in one series of commands!
Already exists - Unix domain sockets. Some shells (in particular some versions of ksh) use them to implement pipes. And, on some platforms (Linux yes, but I think maybe not macOS???) Unix domain sockets support record-oriented operation (SOCK_SEQPACKET). The problem is that for it to work you don’t just need the kernel to support it and the shell to use it, you also need all the utilities to support it too-that’s a big ask.
The idea has been implemented on IBM mainframes (CMS pipelines aka Hartmann pipelines). But that’s a radically different platform, and IBM has never tried porting that to a non-mainframe platform, and nobody has ever sought to directly clone it (although stuff like PowerShell and NuShell share some of its ideas, albeit none of the details)
Thanks for the FYI.
That ought to make life simpler for downstream commands that try to go beyond processing a text stream.
That's not what I mean by record-oriented IO though. That's signalling record boundaries in-band. I'm talking about signalling them out-of-band. So you have record lengths kept separately from the data, and passed around by APIs separately from the data bytes.
Telecoms uses both concepts (in-band signaling and out-of-band signaling) but I guess the Unix developers didn't get the memo ?
Many (but not all) Unix implementations already have support for “record-oriented pipes” in the kernel, it is just that support has rarely been used. Linux has record-oriented Unix domain sockets (SOCK_SEQPACKET), but few use them.
> Telecoms uses both concepts (in-band signaling and out-of-band signaling) but I guess the Unix developers didn't get the memo ?
The original Bell Labs Unix team created STREAMS, which does support true record-oriented IO. Most commercial Unix implementations (such as Solaris and AIX) support it (or at least did at one point). But Berkeley Sockets won the mindshare competition, and open source Unix-likes (such as Linux and BSDs) never added streams support. There was a project to add it to Linux, but Linus was opposed to the idea, so it never got merged, and I think it has since been abandoned.
Even before STREAMS, Unix supported record-oriented IO in the terminal subsystem (cooked mode). But it wasn’t general, it was very specific to the needs of interactive use. STREAMS was intended as a generalisation but it never caught on. So even today all Unix-likes have a purpose-specific (rather than general) record-IO implementation in their tty subsystems, pseudoterminals, etc
ASCII was perfect for table output. All tools had to do when outputting is use the standard existing characters when no TTY is detected, else use tabs/spaces and newlines.
I always wondered why no one uses the ASCII rs and FS codes.
It deals with 99.99% of uses cases that pipes are being used for right now.
That's more than good enough.
If you really needed to output a tree using only rs and fs characters, and since they are only a single byte each, you could cover that 1 in a 1000 use case by using empty fields for depth of a record, and attaching any record to the current parent until the depth changes.
Depth of a record seems useful, but then you'll have to make fields mandatory to indicate between real records and depth. slowing down the parsing.
FS=, RS=; GS=( US=)
The Unix philosophy as usually stated includes the rule "write programs that work together".
Most Unix commands don't work together in any meaningful sense. For example, `ps | kill` will not terminate all processes, as one might naively expect.
I'd say this is a clear violation of both the letter and the spirit of the Unix philosophy.
Tools like xargs exist to fill that void, and it allows the tools themselves to work independently.
Developing a set of tools from scratch that share a strict design principle is much easier than enabling an ecosystem of purpose-built tools developed over decades by external contributors to interoperate with each other. Leaving the exchange format open is a reason this still works so well today. Or would you rather use XML or whatever format was popular 40 years ago, have to adopt a new format whenever the previous one becomes outdated, and deal with compatibility hell when tools support different versions of the format?
Who expects it to behave like that? Quite the assumption.
Expecting automagic inference based on typing is building a system based on assumption. Have fun making breaking changes to a foundational component that every command will rely on. Everyone will assume you want typed data and if you don't accept/generate typed data then what? Will every shell program have to be burdened with this nonsense and require a rewrite?
In the end ps does exactly what it was meant to do: print information on processes. Your assumption is missing the step where you extract the necessary information you want, e.g. the pid. That is where unix philosophy comes in. Your assumption also seems to make foot guns easier as ps|kill should not be that easy.
rm `ls`
kindof work
dt [ "," split ] pls prints split
dt [ "," split ] map pls prints stack underflow
I think I could definitely use this if it had better docs and I could figure out how to.
hello,world,one
maybe,baby,you
should give
world
baby
I know people who can't be bothered to learn these tools and write complete programs to solve problems instead of a shell one-liner.
Looks similar.
Edit: My brain skipped words while typing.
This one of substituting AWK/shell/sed/Perl with a forth-like lang is a good idea in a sense, it doesn't break the flow because presentation comes later and logic is at the beginning of the dt part, with the aforementioned tools you have the logic and output mixed all over the place. I will however still use AWK.
I didn't mean to discredit the work done. It's a big undertaking in any case. The idea and the aim is good, however it breaks the conciseness and reduces the speed of implementation.
> with the aforementioned tools you have the logic and output mixed all over the place.
I think this is a secondary effect of composability, pipe and conciseness requirement.
> I will however still use AWK.
Me too, and this is why I made my prior comment, exactly.
Actually it's exactly the opposite, it's born out of a love for pipes, and shells, and tools like awk. If you know anyone working at Amazon, ask them to search "11 years of work in a weekend" for a tale of shell heroics that I wrote about while I worked there.
dt is intended to be a new tool in the "shell one-liners" category, just with concatenative FP semantics. :) It will not be everyone's cup of tea, and I will still love and use awk when appropriate
Probably dt will never be able to do things that awk can't do... At least for the non-trivial things. But I think it will be able to do some things with a more readable/declarative syntax.
I'll fill this out later, but imagine dt as trying to be a shell-friendly Functional Programming riff on awk, with first-class functions and no need to regex match or BEGIN etc. At the end of the day, assuming it catches on, I suspect choosing dt will probably be more often about taste
Which is the exact point in time when I solve the problem by using a real programming language.
I write shell-scripts when the current tools solve the problem easily. I distribute shell scripts to colleagues (never customers) only when I absolutely do not want to install extra software on their system.
I avoid awk and perl because if I'm going to introduce a second language to a tool, I'm not going to pick the niche ones everyone only learns opportunistically if at all. At that point I'd rather pick something my colleagues are deeply familiar with.
And on a small level, writing these little binaries that truly do one thing and do it well and that I understand intimately is a private joy.
How so? I tried to seriously learn Bash a few days ago, and once I learned about word splitting, [[ ]] vs. [ ], "${MY_VAR}" just to properly reference a variable it seemed even more full of technical debt that Wat-full [1] Javascript. I figured it would be obsoleted by a modern shell language alternative by the time I will be 30 (currenty 18), it's not worth it, and gave up. I think the bar should not be Turing completeness for a programming language to be decent.
There is no 'wat' situation for a tool you really are proficient with.
The help command is the only other resource you need, imo.
push(1); push(2); push(3); multiply-top-of-the-stack(); add-top-of-the-stack();
Then `status upcase pls` would do something like the above, but it calls a "to uppercase" function before printing.
Being able to filter, sort, or transform properties of the objects passed over makes it much more straightforward to work with than bash et al.
The memory overhead with sets of objects and their properties vs vanilla strings is significant though and easy to bump up against when working with large data sets. Best to try to keep all of the processing for that dataset in a single pipeline if you can. But that’s tradeoffs.
I had an idea where I'd make wrappers for all the popular commands that would accept JSON structured data instead of raw binary data and "do the right thing". And that way you could take advantage of it without having to change your shell tooling. And they'd all accept an extra argument called either --structured-out or --unstructured-out which would either emit JSON or render the output back to a "flat" string, as appropriate.
There have been so many nice CLI tools these last 10 years. Quality of life kind of nice. ag/rg, fzf, entr, up, lf...
Go and rust have been appreciated enablers, even though ruby/python/js demonstrated the concepts, with somewhat poor performances and UX.
Did some fancy DB work for them on OS/2 and early AS/400s in the '90s.
Names are hard.
And wait until you hear what the most popular open source alternative to Photoshop is called...
(I got sufficiently competent at perl before really noticing sed and awk existed that I'm pretty terrible at the latter two, so YMMV etc.)
I'd suggest that a functional shell like es-shell is more interesting than this experiment =)
As an aside, I wish I was cool enough for lobste.rs!
> Dt: Duct tape for your Unix pipes
^^^^ Excuse me, is it "duct" or "duck" tape?
I mean sure, "duct tape" and "duck tape" are both fine. "Duct tape" is the more common name today. The older name is "duck tape" after the duck cloth under the adhesive.
As an aside: If you care about such things, make sure to read up on how today's common version became popular. A 51-year-old woman named Vesta Stoudt, mother of 8, mailed her idea for a better ammunition box seal to the president (who approved production) after her bosses didn't do anything with the suggestion.And on a completely unrelated note, one of the greater stories of quasi-forgotten sacrifice of a mother for her son is the story of a woman in 1850s travelling around 2,000 kilometres by foot, by horse, by any means to get her son enrolled into university, dying shortly after: her name was Maria Dmitrievna Mendeleeva, her son's name was Dmitri Ivanovich Mendeleev [3], that Mendeleev.
[1] https://en.wikipedia.org/wiki/Vesta_Stoudt
[2] https://hsm.stackexchange.com/a/13154
[3] https://chemaust.raci.org.au/article/julyaugust-2019/mother%...
The poster probably used the HN bookmarklet which sets the title automatically.