/dev/chat

12:00 AM

@Gilles What I'd like to see is a discussion on meta between people like you and Michael, derobert, goldilocks and the like, who have a deep understanding of kernel hacking. I feel like we haven't really clarified how to draw the line.

Then again, as I said before, that might just be that I don't understand the line.

Michael Homer

System administrators do build kernel modules, apply patches, etc, and I think those questions are on-topic now - they just get closed anyway.

Gilles

@terdon If you're writing code, and it's not just simple scripting that non-programmers can do, it's off-topic.

@MichaelHomer They do? Not that I've seen.

Building kernel modules is on-topic, of course, and I don't see such questions getting closed as off-topic.

Writing kernel modules is off-topic, and those questions tend not to get close, and I never understood why.

terdon

@Gilles Where building means compiling, right? Not writing.

Gilles

@terdon yes

terdon

How about modifying a module's source to add minor functionality? That seems to me to be a bit of a grey area.

Or, "How does functionX of the kernel API work?"

Michael Homer

12:04 AM

I don't think there's a clear line here, but the "no programming questions" rule leads to kneejerk responses, and migration is the one kind of closure we can't fix afterwards

Gilles

@terdon off-topic

@terdon on-topic, because it's useful when you're trying to understand why your system isn't behaving the way you want

The question is, what is the role of the asker? User or administrator → Unix & Linux, programmer → Stack Overflow

Michael Homer

I'd also like distribution packaging to be on topic, and it's a bit murky now

Gilles

@MichaelHomer it is on-topic

terdon

Well, the two categories are quite connected. I'd consider something like "Here's my code, it's supposed to do X by using API functions but functionFOO() isn't behaving the way I expect it to" to be on topic. It's still programming but it's very *nix.

@MichaelHomer That's 100% on-topic.

Michael Homer

@Gilles Well, yes, it is, but questions in that area are quite often about compiling or patching something

Gilles

12:07 AM

@terdon and then you get into silly distinctions like “unlink is on-topic but remove is off-topic”

terdon

@Gilles Yes, which is why I'm not entirely clear on this.

Gilles

@MichaelHomer Compiling someone else's code is on-topic. Patching is on-topic. And I'm not noticing these questions being closed as off-topic. Examples please.

terdon

@MichaelHomer Compiling and applying existing patches are certainly on topic. It only gets murky when the issue is with your own code. If you're trying to make someone else's package work, you're fine.

Michael Homer

I'll make a note next time I see one in the queue

terdon

Please do. Also feel free to flag questions you feel are in the process of being incorrectly closed.

Michael Homer

12:16 AM

I'm looking through migrated-out questions now, and the main takeaway is that lots of these should just have been closed outright.

Faheem Mitha

@MichaelHomer Distribution packagind is definitely on-topic. As far as I know, that has never been at issue.

@terdon Which two categories?

@terdon I think that's fine, personally. But like I said, there is no concensus about that. Those sorts of questions are actually (or could be) quite interesting.

Michael Homer

I think I was a bit unclear there. It's clearly on-topic, but a reasonable subset of those questions are about build errors or configuration, which sets people off.

Faheem Mitha

@MichaelHomer I don't see why it sets people off. But I'll take your word for it. Actually, I don't thinK I've ever seen a packaging question be closed as off-topic. Do you have an example?

Granted, questions about kernel modules are not about the C API.

Michael Homer

No, I'm actually looking through outward migrations now and there aren't as many as I expected. Perhaps they actually are getting stopped in the queue.

Wearing my distribution-maintainer's hat, I often wrote patches to other people's code (to fix paths, compile in the sandbox, and suchlike), and I'm uncertain of where those stand. They're not "existing patches", so it sounds like a no from the room.

Faheem Mitha

@MichaelHomer No, I think they're fine. And what distribution do you maintain?

Michael Homer

12:32 AM

It's not an existing patch, and it's a problem I created for myself by trying to compile in a sandbox/with funny paths/..., so it's a bit of a grey area. At some point patching really does just become writing entirely new code. There actually is a distinction to draw somewhere there.

Faheem Mitha

@MichaelHomer If it's to get a package to build, that's part of distribution-specific packaging.

But I don't think I've ever seen a question like that here. It would be way too specialist for this site, whether it was on topic or not.

People with such questions typically go elsewhere if they need help.

Michael Homer

Indeed, it's not a common query. Certainly not close to the level of "do my genomics processing for me with awk".

To the extent that the ones I've seen the the queue don't seem to have actually been migrated in the end it doesn't seem like there is a problem.

Faheem Mitha

Personally, I'd like to see some Unix programming type questions in preference to yet another brainless "manipulate my text file so it does something totally uninteresting" questions. Though maybe it is politically incorrect to say so.

Gilles

@FaheemMitha stackoverflow.com/questions/tagged/c+unix

Faheem Mitha

@Gilles Thank you.

To be clear, I meant on this site.

Of course, Unix programming questions can be brainless too.

Some of those questions would be perfectly fine here, imo. E.g.

2

Q: C: Closing File Descriptors

how would I go about properly closing a file descriptor? I currently have to write a simple unix shell. For example, if the user entered sort < someFile, I have the following code: freopen(commandArg[<location + 1],"r",stdin); executeArg(commandArg); fclose(stdout); When I execute the command ...

Though the author didn't bother to answer his own question.

See also stackoverflow.com/q/35169038/350713

Michael Homer

12:43 AM

I agree with that, but whether those questions would have been closed here remains unseen, of course

Faheem Mitha

@MichaelHomer I'm watching your 2015 talk on youtube. But aren't there a lot of teaching languages already?

Michael Homer

There are quite a few

The talk gets a little better once I stopped taking interruptions from the floor, I think

Faheem Mitha

Presumably you think you're bringing something new to the table.

Michael Homer

The overarching goal is more one of drawing together currently-disparate groups than of directly improving, I think. I'm not sure whether it's effective or not

The 2010 talk is more relevant to here

Faheem Mitha

@MichaelHomer Ok. This is a topic I know nothing about.

Michael Homer

12:50 AM

I would personally have hewn closer to the ed-psych literature if I'd had my way with everything

Faheem Mitha

@MichaelHomer I don't get that reference. Are you still working on Grace then?

Personally, I think more people should be learning Common Lisp or something similar out of the gate.

Michael Homer

It'd be less broad, but more effective. Or at least, if it weren't, that would be an interesting result vis-a-vis accuracy and generalisability of that literature.

Racket is the more Lispy teaching language

Faheem Mitha

@MichaelHomer To be clear, the term ed-psych literature means nothing to me.

@MichaelHomer True. But CL is what people actually use. And it's not hard to learn.

Michael Homer

Sorry. Educational psychology.

Faheem Mitha

@MichaelHomer Yes, I sort of guessed that. But I don't know what viewpoint that represents.

Michael Homer

12:54 AM

Lisp people are very keen on Lisp. If people are going to move on to Java or C or something, though, I don't think it's a good start.

Faheem Mitha

@MichaelHomer Well, it's a good language. More people should use it. And they're more likely to use it if they learn it early.

Michael Homer

No particular viewpoint, just decades of experimental results

Faheem Mitha

@MichaelHomer Ok.

I'm not a Lisp person. But I still think it's a good idea.

Michael Homer

@FaheemMitha That isn't much of a reason to teach with it, to be honest.

Faheem Mitha

@MichaelHomer <Shrug>. That's debatable. But I guess if you're professionally involved in the area, you have your professional opinion.

Having said that, people are perhaps more likely to appreciate Lisp if they come to it after having discovered the deficiencies of other languages. As I did.

Java. C/C++ users typically don't even know there are alternatives.

I don't have a formal CS background, otherwise I might have known about CL earlier.

Michael Homer

12:58 AM

Producing more Lisp programmers just isn't a general good. If it's useful for them, they'll use it eventually.

Faheem Mitha

As it is, I discovered its existence in 2006.

Michael Homer

If you want to teach people then you want something that helps them learn.

Faheem Mitha

I think CL is a very educational language. And probably Racket too, of course.

Michael Homer

Or, you just want to pick arbitrarily and accept that you'll lose people, which is a popular approach.

Faheem Mitha

It illustrates lots of basic programming concepts with a great deal of clarity. Without the burden/overhead of excessive syntax.

@MichaelHomer I don't think programming is that hard, myself.

But maybe your purpose/intentions are different?

Is the idea to improve general programming literacy?

Michael Homer

1:00 AM

People who are programmers tend to think that way, yes

They also find learning new languages easy

Faheem Mitha

@MichaelHomer Think what way?

And I don't consider myself a programmer. Though I've written code, certainly.

Michael Homer

Think it's just easy

Faheem Mitha

@MichaelHomer Ah. Actually, I wrote "I don't think programming is that hard", actually.

I wouldn't use the word "easy".

Michael Homer

Or that

Faheem Mitha

But, again, is your intention, or the intention of the project, to improve programming literacy among the general population?

Michael Homer

1:03 AM

I don't have anything to say about the intentions of the project

Faheem Mitha

In that case, it might make sense to streamline the process. Reduce the level of obstacles.

Certainly, most "real" programming languages make no concessions to the needs of learners.

Michael Homer

I would like to improve the learning process for novice programmers, generally

Faheem Mitha

Ok.

A language like C++ is actually quite horrible for something who is trying to learn it. Then again, C++ is a horrible language generally. Like walking through a forest of thorns naked.

Michael Homer

People forget what it was like starting out.

Faheem Mitha

@MichaelHomer Starting out programming? The first language I tried to learn was C. It was a nightmare. That was in 1997. Kind of late in the day.

Michael Homer

1:13 AM

I'm not convinced that language really matters all that much (when there's actual structured teaching going on).

Faheem Mitha

1:29 AM

@MichaelHomer You mean the teaching language of choice?

Michael Homer

Yes

Faheem Mitha

I think some languages are easier to learn than others. E.g. Python is easier to learn than C.

But in my case, nobody taught me anything. I was trying to learn C in a semester to use in a numerical programming class. And I already had a lot of other things going on. It was horrible.

The instructor was a Fortran user, I think. I think he knew C, though.

Anyway, I got help from a friend in another country, the Uk. But no local help.

I still have the correspondence.

Faheem Mitha

3:02 AM

@terdon You originally introduced me to the Suspender Chrome/Chromium extension. For some reason it's stopped suspending recent pages. Any idea why this might have happened?

Or, indeed, how to debug it?

Hmm. Excessive number of tabs. I think I need to take a timeout and do some mass deleting.

terdon

11:18 AM

@FaheemMitha No idea beyond checking the settings.

Pandya

11:36 AM

@muru

why not simply grep Hello -r?

Pandya

11:49 AM

* doesn't match files leading with dot. Do you know about another wild-card that matches everything? @terdon

terdon

@Pandya for bash, use the dotglob option: shopt -s dotglob; echo *

Or use two globs: echo .* *

Pandya

ok. btw, How grep -r works for dot-files?

@cuonglm How about : find . -maxdepth 1 -type f -exec grep -l Hello '{}' \; ?

cuonglm

12:17 PM

@Pandya It's not POSIX, and not optimization, you call each grep process for a file found

@Pandya Updated unix.stackexchange.com/a/264543/38906

Pandya

@cuonglm ok let me check

$ find . ! -name . -prune -type f ! -name '.*' -exec grep Hello /dev/null {} +
./file2:Hello
./file1:Hello

@cuonglm ^^ still not getting .file3

$ cat .file3
Hello

@SHW By the way, I've revised that answer

By the way @terdon can you check:

for i in /usr/share/doc/*/copyright; do grep -l "General Public License" $i; done | wc -l

And

sudo find /usr/share/doc -name copyright -type f -exec grep -l "General Public License" '{}' \; | wc -l

I'm getting 1768 for first and 1714 for second

actually I want to add second command here but surprised to see different result

Have you any idea why getting different result?

terdon

12:34 PM

What system are you on? Do you really have so many copyright files? I only have one on my Arch and 7 on my Debian.

Ah, no, Debian has loads.

Pandya

Trisquel GNU/Linux

If interested meta.unix.stackexchange.com/a/3879/66803

And deepppandya.wordpress.com/2016/02/19/how-i-do-my-computing

terdon

Anyway, to check, just print the output and compare them. Do echo /usr/share/doc/*/copyright >a and find /usr/share/doc -name copyright -type f > b and compare the output.

@Pandya This is now status-completed

Pandya

@terdon Thanks for knowing!

:D

I had also wasted bounty see meta.stackexchange.com/posts/254566/revisions

Done!

terdon

@Pandya OK, I think I figured it out. I also had different results on my Debian and it's because of links. The glob approach will expand all links. For example:

$ ls -il $(printf "%s\n" usr/share/doc/*/copyright | grep wpa)
287423 -rw-r--r-- 1 root root 14249 Sep 16  2014 usr/share/doc/wpa_supplicant/copyright
287423 -rw-r--r-- 1 root root 14249 Sep 16  2014 usr/share/doc/wpasupplicant/copyright

Note that those two have the same inode number, they're the same file. That's because:

$ ls -l usr/share/doc/wpa_supplicant
lrwxrwxrwx 1 root root 13 Jan 19  2013 usr/share/doc/wpa_supplicant -> wpasupplicant

Since find is searching for files, it will i) ignore files that are links and ii) will only find the link's target since that is the only existing file.

The glob on the other hand, will list both usr/share/doc/wpa_supplicant/copyright and usr/share/doc/wpasupplicant/copyright despite the fact that wpa_supplicant is a link to wpasupplicant and so is the same file.

Anyway, the find command is correct.

Pandya

right

terdon

12:48 PM

And, next time, don't use a loop for the glob! That will just slow things down. Use the glob directly:

grep -l "General Public License" /usr/share/doc/*/copyright

Pandya

Thanks

terdon

np

Pandya

By the one advantage of find : It also include files like /usr/share/doc/ca-certificates/examples/ca-certificates-local/debian/copyright which can't be found with /usr/share/doc/*/copyright

should we include it? or we should set maxdepth with find?

terdon

By the way, @Pandya, what's your avatar? I just noticed that the last letter is Pa (or at least, the sanskrit Pa). The line on top would make an I (or O, I have forgotten my sanskrit) but it would affect the 1st letter, so it can't spell Pandya, right?

@Pandya The other advantage is that it actually finds the right number. Also, you can use globstar: shopt -s globstar; grep -l "General Public License" /usr/share/doc/**/copyright.

Pandya

Pandya is my surname and my name is Deep

My avatar shows Deep in Devnagari (Sanskrit/Hindi) script

SHW

12:52 PM

@Pandya Check the new answer

terdon

A, so the line makes E. But isn't the last letter still "Pa"? Don't you need the squiggly line to remove the A sound?

Pandya

@SHW Actually find is recommended unix.stackexchange.com/revisions/264067/3

Devanagari

Devanagari (/ˌdeɪvəˈnɑːɡəriː/ DAY-və-NAH-gər-ee; Hindustani: [d̪eːʋˈnaːɡri]; देवनागरी devanāgarī a compound of "deva" [देव] and "nāgarī" [नागरी]), also called Nagari (Nāgarī, नागरी), is an abugida (alphasyllabary) alphabet of India and Nepal. It is written from left to right, has a strong preference for symmetrical rounded shapes within squared outlines, and is recognisable by a horizontal line that runs along the top of full letters. In a cursory look, the Devanagari script appears different from other Indic scripts such as Bangla, Oriya or Gurmukhi, but a closer examination reveals they are very...

terdon

@Pandya Ah, I see, thanks. So प here is just an a sound. In sanskrit, it was pa, that's what confused me.

Pandya

by the way, where do you live?

terdon

Ah, yes, there it is in the next table.

@Pandya Greece now.

Pandya

1:01 PM

By the way, you know He is you who introduced/call me to chat-room first time on SE network and I learnt chat feature @terdon!

terdon

Oh? cool :)

Pandya

It was : askubuntu.com/questions/460993/…

And chat.stackexchange.com/transcript/201?m=15340168#15340168 was my first message

terdon

heh

cuonglm

@Pandya: What do you mean? not getting .file3 is what you want in your question?

@Pandya: Ah, sorry

I have mis-read it, fixed

Pandya

At that time You @terdon and @Avinash Raj are competitor (for sed,awk,perl etc answer) example I've first accepted his answer, then you improved your and I accepted your answer. At that time I was not so aware of Unix&Linux.SE

@cuonglm working fine; +1

In brief that was probably my first message on chat on SE network! which was for @terdon!!

Faheem Mitha

2:52 PM

@terdon The settings look the same as always. Maybe I just have too many tabs. Maybe there's some undocumented limitation? I don't see why, though.

Pandya

3:21 PM

After knowing that "grep doesn't ignore anything. *, by default, does not match files with a leading .", should I edit my question (like wild-card * ignores files starting with dot) or should leave it as it is?

Jeff Schaller

4:32 PM

If anyone has any thoughts regarding the trivial point of tag wiki default text, feel free to @ send them here, or join the chat room I probably messed up

the "this tag has no wiki" default text says "...along with guidelines on its usage" -- yet my most recent edits were updated to put the tag usage in the excerpt (up top) versus down in the wiki.

maybe meta would be a better place, but if anyone sees this and has a preference, chime in! :)

Faheem Mitha

Hmm, dpkg -l | grep php returns nothing. Does that mean I don't have PHP installed on my system?

Jeff Schaller

certainly seems (to me) that way -- packages.debian.org/jessie/php5 refers to php* variations

Faheem Mitha

Well, I just assumed PHP had crept onto my machine. If it hasn't, well,...go me!

N Altun

5:02 PM

@shaggy Is a Chromebook all you have access to? I wish I had more knowledge of using a Chromebook as a native Linux (OS) box. Any ideas on which distro you're settling on?

Faheem Mitha

6:08 PM

This one looks like a VTC:

1

Q: Root password is asked for anything after dist-upgrade

I'm using Debian Stretch and today I did apt-get upgrade && apt-get dist-upgrade. After that, nearly every action is started to ask root password, including external monitor plug/unplug, USB harddisk mount, suspend, etc... Why is that? How can I trace this issue?

debian upgrade authorization

No idea why it was upvoted...

shaggy

7:41 PM

@NAltun I have pretty much have access to anything at this point, so i'm not limited to a chromebook. I just don't need something super fancy to learn linux on, as well as keeping it financially practical, the cheaper the better. But with that kept in mind, It would be good for all the hardware to be well supported OOTB.

I'm only considering a chromebook due the fact that chromeOS is linux based so the hardware support is there, its a modern machine, and is super portable. If there is a better option i'm totally open to it.

Before my discovery of the chromebook, I was planning on going down the thinkpad path.

Michael Homer

9:35 PM

Returning to the topic of questions over-eagerly migrated to SO at the mere hint of programming: this one

Gilles

@MichaelHomer yeah, that's a strange one. I even voted to close it as off-topic on SO.

Questions about general computing hardware and software are off-topic for Stack Overflow unless they directly involve tools used primarily for programming. You may be able to get help on Unix & Linux. — Gilles Jan 7 at 23:49

slm hasn't been in chat lately

Michael Homer

Yes, I saw. I don't think it's really off-topic either place, but it fitted just fine here.

Faheem Mitha

10:46 PM

@MichaelHomer I don't really understand what he's trying to do there.

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