Wednesday, May 4, 2022

CC0 vs GPL

I've been writing little bits and pieces of my own code for many years now. And I've been releasing it as CC0 ("public domain"; see below). I've received a bit of criticism for it, and I guess I wanted to talk about it.

I like to write software. And I like it when other people benefit from my software. But I don't write end-user software, so the only people who benefit from my code are other programmers. But that's fine, I like a lot of programmers, so it's all good.

There are different ways I could offer my software. Much open-source software is available under a BSD license, an Apache license, or an MIT license. These differ in ways that are probably important to legal types, but for the most part, they mean that you can use the code for pretty much any purpose as long as you give proper attribution to the original source. So if I write a cool program and use some BSD code, I need to state my usage of that code somewhere in my program's documentation.

So maybe I should do that. After all, if I put in the effort to write the code, shouldn't I get the credit?

Yeah, that and a sawbuck will get me a cup of coffee. I don't think those attributions are worth much more than ego-boosting, and I guess my programmer ego doesn't need that boost.

With the exception of the GNU Public License (GPL), I don't think most open source ego-boosting licenses buy me anything that I particularly want. And they do introduce a barrier to people using my code. I've seen other people's code that I've wanted but decided not to use because of the attribution requirement. I don't want the attributions cluttering up my documentation, and adding licensing complications to anybody who wants to use my code. (For example, I was using somebody else's getopt module for a while, but realized I wasn't giving proper attribution, so I wrote my own.)

But what about GNU?

The GPL is a different beast. It is intended to be *restrictive*. It puts rules and requirements for the use of the code. It places obligations on the programmers. The stated goal of these restrictions is to promote freedom.

But I don't think that is really the point of GPL. I think the real point of GPL is to let certain programmers feel clean. These are programmers who believe that proprietary software is evil, and by extension, any programmer who supports proprietary software is also evil. So ignoring that I write proprietary software for a living, my CC0 software could provide a small measure of support for other proprietary software companies, making their jobs easier. And that makes me evil. Not Hitler-level evil, but at least a little bit evil.

If I license my code under GPLv3, it will provide the maximum protection possible for my open-source code to not support a proprietary system. And that might let me sleep better at night, knowing that I'm not evil.

Maybe somebody can tell me where I'm wrong on this. Besides letting programmers feel clean, what other benefit does GPL provide that other licenses (including CC0) don't?

I've read through Richard Stallman's "Why Open Source Misses the Point of Free Software" a few times, and he keeps coming back to ethics, the difference between right and wrong. Some quotes:

  • "The free software movement campaigns for freedom for the users of computing; it is a movement for freedom and justice."
  • "These freedoms are vitally important. They are essential, not just for the individual users' sake, but for society as a whole because they promote social solidarity—that is, sharing and cooperation."
  • "For the free software movement, free software is an ethical imperative..."
  • "For the free software movement, however, nonfree software is a social problem..."
I wonder what other things a free software advocate might believe. Is it evil to have secret recipes? Should Coke's secret formula be published? If I take a recipe that somebody puts on youtube and I make an improvement and use the modified recipe to make money, am I evil? What if I give attribution, saying that it was inspired by so-and-so's recipe, but I won't reveal my improvement? Still evil?

How about violin makers that have secret methods to get a good sound? Evil?

I am, by my nature, sympathetic to saying yes to all of those. I want the world to cooperate, not compete. I used to call myself a communist, believing that there should be no private property, and that we should live according to, "From each according to his ability, to each according to his needs". And I guess I still do believe that, in the same way that I believe we should put an end to war, cruelty, apathy, hatred, disease, hunger, and all the other social and cultural evils.

Oh, and entropy. We need to get rid of that too.

But none of them are possible, because ... physics? (That's a different subject for a different day.)

But maybe losing my youthful idealism is nothing to feel good about. Instead of throwing up my hands and saying it's impossible to do all those things, maybe I should pick one of them and do my best to improve the world. Perhaps the free software advocates have done exactly that. They can't take on all the social and cultural ills, so they picked one in which they could make a difference.

But free software? That's the one they decided was worth investing their altruism?

Free software advocates are always quick to point out that they don't mean "free" as in "zero cost". They are referring to freedoms - mostly the freedom to run a modified version of a program, which is a freedom that is meaningless to the vast majority of humanity. I would say that low-cost software is a much more powerful social good. GPL software promotes that, but so do the other popular open-source licenses. (And so does CC0).

So anyway, I guess I'm not a free software advocate (big surprise). I'll stick with CC0 for my code.

What is CC0

The CC0 license attempts to codify the concept of "public domain". The problem with just saying "public domain" is that the term does not have a universally agreed-upon definition, especially legally. So CC0 is designed to approximate what we think of as public domain.

Tuesday, February 15, 2022

Pathological cases

Jacob Kaplan-Moss said something wonderful yesterday:

Designing a human process around pathological cases leads to processes that are themselves pathological.

This really resonated with me.

Not much to add, just wanted to share.

Thursday, February 3, 2022

Nice catch, Grammarly

 I was writing an email and accidentally left out a word. I meant to write, "I've asked the team for blah...". But I accidentally omitted "asked", so it just said, "I've the team for blah...".

Grammarly flagged "I've", suggesting "I have". Since my brain still couldn't see my mistake, I thought it was complaining about "I've asked the team...". I was about to dismiss, but decided to click the "learn more" link. It said that, except in British English, using the contraction "I've" to express possession sounds unnatural or affected. As in: "Incorrect: I've a new car".

Ah HAH! That triggered me to notice the missing word "asked". I put it in, and Grammarly was happy. I consider this a good catch. Sure, it misdiagnosed the problem, but it knew it was a problem.

Thanks, Grammarly!

Wednesday, January 5, 2022

Bash Process Substitution

I generally don't like surprises. I'm not a surprise kind of guy. If you decide you don't like me and want to make me feel miserable, just throw me a surprise party.

But there is one kind of surprise that I REALLY like. It's learning something new ... the sort of thing that makes you say, "how did I not learn this years ago???"

Let's say you want the standard output of one command to serve as the input to another command. On day one, a Unix shell beginner might use file redirection:

$ ls >ls_output.tmp
$ grep myfile <ls_output.tmp
$ rm ls_output.tmp

On day two, they will learn about the pipe:

$ ls | grep myfile

This is more concise, doesn't leave garbage, and runs faster.

But what about cases where the second program doesn't take its input from STDIN? For example, let's say you have two directories with very similar lists of files, but you want to know if there are any files in one that aren't in the other.

$ ls -1 dir1 >dir1_output.tmp
$ ls -1 dir2 >dir2_output.tmp
$ diff dir1_ouptut.tmp dir2_output.tmp
$ rm dir[12]_output.tmp

So much for conciseness, garbage, and speed.

But, today I learned about Process Substitution:

$ diff <(ls -1 dir1) <(ls -1 dir2)

This basically creates two pipes, gives them names, and passes the pipe names as command-line parameters of the diff command. I HAVE WANTED THIS FOR DECADES!!!

And just for fun, let's see what those named pipes are named:

$ echo <(ls -l dir1) <(ls -1 dir2)
/dev/fd/63 /dev/fd/62


(Note that echo doesn't actually read the pipes.)


The "cmda <(cmdb)" construct is for cmda getting its input from the output of cmdb. What about the other way around? I.e., what if cmda wants to write its output, not to STDOUT, but to a named file, and you want that output to be the standard input of cmdb? I'm having trouble thinking here of a useful example, but here's a not-useful example:

cp file1 >(grep xyz)

I say this isn't useful because why use the "cp" command? Why not:

cat file1 | grep xyz

Or better yet:

grep xyz file1

Most shell commands write their primary output to STDOUT. I can think of some examples that don't, like giving an output file to tcpdump, or the object code out of gcc, but I can't imagine wanting to pipe that into another command.

If you can think of a good use case, let me know.


Here's something that I have occasionally wanted to do. Pipe a command's STDOUT to one command, and STDERR to a different command. Here's a contrived non-pipe example:

process_foo 2>err.tmp | format_foo >foo.txt
alert_operator <err.tmp
rm err.tmp

You could re-write this as:

process_foo > >(format_foo >foo.txt) 2> >(alert_operator)

Note the space between the two ">" characters - this is needed. Without the space, ">>" is treated as the append redirection.

Sorry for the contrived example. I know I've wanted this a few times in the past, but I can't remember why.

And for completeness, you can also redirect STDIN:

cat < <(echo hi)

But this is the same as:

echo hi | cat

I can't think of a good use for the "< <(cmd)" construct. Let me know if you can.


I'm always amused when I learn something new and pretty quickly come up with a good use for it. I had some files containing a mix of latency values and some log messages. I wanted to "paste" the different files into a single file with multiple columns to produce a .CSV. But the log messages were getting in the way.

paste -d "," <(grep "^[0-9]" file1) <(grep "^[0-9]" file2) ... >file.csv

Done! :-)