/dev/chat

4:01 PM

@terdon I don't think you should loose your votes because of a migration -- they get transferred to the destination site. The double voting is a slightly gray area maybe. But I though it would be great if we start asking coding questions, upvote them here, then migrate them and upvote them again. I could use some S.O. points. The linux tag gang there seem a somewhat surly, stingy bunch ;)

Faheem Mitha

@Patrick :-) Are you talking to yourself?

goldilocks

@Tim As someone who has used tmux but never screen, I of course prefer tmux. I think maybe it has more bells and whistles display wise? Which was all I actually used it for and also why I mostly gave it up -- having multiple panes just gets me flustered. I think people who use screen use it more specifically just for detaching and reattaching processes.

Faheem Mitha

Hi guys.

@Tim I doubt it makes much difference, at least if you are doing basic things.

Like @derobert says, try them both.

I was over in Rpi chat, talking to one Rpiawesome. He was quite helpful.

I tried a local salesperson. She was predictably completely useless. It's India, after all.

I always seem to wind up using -9 myself.

If I pause with ^Z, it is by design that only -9 works?

Or should a lesser signal still work?

goldilocks

@FaheemMitha Yes, s/he is very enthusiastic. I feel bad about not contributing there more mostly because of that person.

Tim

I constantly use emacs, and less often vi (mostly in less). Which will work better for these editors: tmux or screen

Faheem Mitha

4:07 PM

@Tim Again, doubt it makes a difference.

Tim

is there conflict in key bindings?

goldilocks

@FaheemMitha (I mean I feel bad about not contributing, not that I don't contribute because of Rpiawesomeness, lol).

Faheem Mitha

The only thing is that keybindings might clash, I guess, so you might have re- configure them.

@goldilocks Right. I thought you were active on that site, though.

Tim

yeah, looking for less conflict one

Faheem Mitha

@Tim I suggest some experimentation. You're not going to get a sensible reply to the question: screen vs tmux. personally, i've only ever used screen, and it works fine. There were some forks floating around - wonder what happened to them.

Apparently the screen maintainer was super-slow accepting patches. Maybe still is. It's GNU, after all.

tscreen one was called.

code.google.com/p/tscreen

" Upstream screen has been progressing lately, and I prefer tmux anyway."

@Tim there you go, steve prefers tmux. :-)

Tim

4:12 PM

Are you saying the author of gnu screen prefer tmux?

Ramesh

Will there be any group known as dialout by default?

Faheem Mitha

Crap, I got an invitation to review a manuscript.

Tim

by "fork", it is not gnu screen, isn't it

Faheem Mitha

@Tim No, no. That's from the guy who forked it. Steve Kemp. It was a joke

@Tim fork of gnu screen, so not itself gnu screen.

@Ramesh ?

Ramesh

@FaheemMitha, for this question.

0

Q: how to determine the permissions of groups?

When you invoke sudo, it prompts for password and then checks the /etc/sudoers configuration file to see if the user is permitted access to run the command. /etc/sudoers is the sudo configuration file that enables certain users or groups to run certain commands. For example, below we make the us...

sudo

goldilocks

4:15 PM

@FaheemMitha I was for a while but my expertise is really all linux oriented; a high percentage of the questions there would be much, much better off here -- some of them do get moved, but the mods resisted a real migration path. I think that and some other issues mean it is sort of destined to remain in beta limbo forever. It might have been better as a more general "dev board" site to include stuff like Beagle Bone and Arduino, but people resisted that idea too.

Faheem Mitha

@goldilocks I see. That's a pity. I think a more general micro-electronics board would be better.

If micro-electronics is the right term.

@Ramesh well, generally the groups are typically just given file-type permissions on relevant devices. It isn't exactly sophisticated.

If that is what he is asking, it's not totcally clear. E.g. dialout is given write permissions on whatever modem-type devices are defined, serial lines or whatever

David Freitag

There was Embedded.SE. We got it afloat, but we lost the paddles shortly after and sank.

Faheem Mitha

@DavidFreitag That was a superset of Rpi.sx, surely?

goldilocks

@FaheemMitha There is the EE board: electronics.stackexchange.com which has raspberry-pi, arduino, and beagleboard, etc. tags. But then there's a whole separate Arduino beta too: arduino.stackexchange.com which I'm sure I remember someone approaching the rpi board and saying it should be changed to be inclusive, but they didn't want that...

Faheem Mitha

@Ramesh faheem@orwell:/dev$ ls -lah | grep dialout
crw-rw---T 1 root dialout 4, 64 Jul 22 22:45 ttyS0
crw-rw---T 1 root dialout 4, 65 Jul 22 22:45 ttyS1
crw-rw---T 1 root dialout 4, 66 Jul 22 22:45 ttyS2
crw-rw---T 1 root dialout 4, 67 Jul 22 22:45 ttyS3

For example

David Freitag

4:25 PM

@FaheemMitha No, Embedded was meant to be a very in depth site. It wasn't about using dev boards like the Rpi or the beagle bone, but more oriented towards the design and engineering of embedded systems

Faheem Mitha

@goldilocks Weird.

@DavidFreitag I see.

Surprised it didn't take off. There must be tons of hobbyist devs out there.

Gnouc

@Tim: See unix.stackexchange.com/questions/146913/is-used-only-with-cd for my answer about your comment with - in cd

David Freitag

But major issues came about and arguments with the EE.SE people started.

goldilocks

@DavidFreitag I hope blows were exchanged :|

David Freitag

@FaheemMitha Lack of committers. Less than 50% of overall people who committed to the proposal actually participated in CB

Ramesh

4:27 PM

@FaheemMitha thanks. I do not see the group in RHEL. Is it OS specific?

Faheem Mitha

@Ramesh It shouldn't be. Since udev (sic?) now creates devices dynamically on demand, maybe those rules have changed. I dunno. I added a stab at a reply to that question. I may be missing the point entirely, though.

@DavidFreitag Ok, maybe just difficulty reaching people. The SE community is getting larger, but there are still lots of people who don't use it for whatever reason.

Patrick

@FaheemMitha I might be. Mental stability is in question.

Faheem Mitha

@Patrick heh.

David Freitag

@FaheemMitha We rebooted the proposal. I haven't checked the progress in a few days though.

Faheem Mitha

So, here is a question. Is ttyS0 created by udev, or hardwired?

@DavidFreitag is that allowed?

David Freitag

4:32 PM

@FaheemMitha Idunno. Ask Gilles.

72

Embedded Systems Programming and Design

Proposed Q&A site for professionals and enthusiasts of embedded hardware and software. Created in lieu of the closed Embedded Programming and Design, this is a reboot.

Currently in definition.

Faheem Mitha

@DavidFreitag Because Gilles knows everything, or for a more particular reason?

goldilocks

@DavidFreitag Nice.

casey

@FaheemMitha If you are running udev, shouldn't all the devices in dev be created by udev? Can you mix udev with mknod? I don't really know.

derobert

You can still create devices with mknod... That's how udev makes them.

udev manages a tmpfs by mknod and unlink, basically

lgeorget

udev is a daemon, mknod is a system call

so there are not really comparable

derobert

4:41 PM

Well, I guess it does mkdir and link as well. But yes, typically, ttyS0 would be created by udev

Faheem Mitha

@casey I don't either. Is there a default list somewhere, perhaps?

lgeorget

@casey but you're right @casey, in the sense that it should not be necessary to create supplementary devices once udev has populated /dev. But sometimes, it is, especially if you do experimentations.

Faheem Mitha

Actually serial devices are not used much any longer, and I don't have any attached to my machines, but the devices are still there.

casey

@lgeorget thats more what I was getting at, just poorly worded

Faheem Mitha

@casey how are you doing? how's the baby?

lgeorget

4:44 PM

@casey ok, then we understand each other :D

casey

@FaheemMitha serial devices are still out there! And as I learned a few months ago, screen is great at talking over a serial port

lgeorget

There are heavily used in the industry.

Faheem Mitha

@casey Oh, what are they used for?

@lgeorget Ok. For what?

lgeorget

@FaheemMitha sensors, robots...

Faheem Mitha

@lgeorget oh

lgeorget

4:46 PM

casey

@FaheemMitha communicating :)

lgeorget

this kind of stuff too. Even if they now have a network connection too.

Faheem Mitha

@lgeorget What is this?

casey

I had to configure a utilite ARM thing's uboot and the easiest way was via null modem cable

the problem was, I didnt have a null modem cable

David Freitag

@FaheemMitha Because he's pretty much been the driving force behind it

casey

4:47 PM

so I built one

lgeorget

@FaheemMitha a programmable robot

casey

David Freitag

And also he's a pretty seasoned SE member

Faheem Mitha

@DavidFreitag Oh

@lgeorget I see.

@DavidFreitag That's an understatement.

David Freitag

@casey That looks quite a lot like my desk :]

goldilocks

4:49 PM

@FaheemMitha I think there are also a lot of eensy embedded type things that run linux and have only a serial port for communication. Actually if you want to flash a router, a serial port can be a last resort failsafe there: you can open the case and there's pins for it, they are used during the original manufacture.

Faheem Mitha

@casey Wow, is that your setup?

casey

@FaheemMitha he's crawling everywhere

Faheem Mitha

@goldilocks I see. I think I had a modem once, and it used to use those things, but it has been a long time. I stopped using a modem in 2003.

goldilocks

@lgeorget I hope it doesn't escape.

Faheem Mitha

@casey That's nice. Not walking yet?

lgeorget

4:51 PM

@goldilocks Fortunately, they didn't give it legs :-)

goldilocks

Bastards.

David Freitag

@lgeorget So, they gave it tank treads instead, right?

casey

@FaheemMitha that particular cable was a db9->rj45 modular adapter -> cat 5 -> rj45->db25 modular adapter, wired straight through to that point. The other end is a db9 to db25 adapter and the bit in the middle is a db25 motherboard header. The null modem magic is in the wiring between the db25 modular adapter and the motherboard header

goldilocks

@DavidFreitag Better yet, the voice of the Black Knight from Monty Python's Holy Grail, if you know that one.

Faheem Mitha

@casey And this is used for?

David Freitag

4:52 PM

@goldilocks I love that movie

lgeorget

@DavidFreitag ^_^

Faheem Mitha

@DavidFreitag As long as it doesn't look like Arnold S.

casey

@FaheemMitha to connect my computer to the serial port on a ARM device so I could get it to boot

Faheem Mitha

@casey Oh, boot the ARM device, right?

David Freitag

@casey Maaaan. You guys need to hop on the 0.5" header train while it's still in town :b

casey

4:54 PM

@DavidFreitag I'm not usually messing with that stuff, but I do have a box full of nothing but modular adapters, adapters and cables with odd terminations, just for an occasion like that

David Freitag

@casey Yeah, same here. I rarely work with that stuff, but we still sell instruments that were designed in the late 80's that need the occasional debugging

lgeorget

@casey And then came the USB, and they saw it was good

casey

@DavidFreitag my box is all loose ends from the late 90's when I worked for a company deploying AIX based point-of-sale solutions. I got to setup the RS/6000, the portservers and wire all of the rj45-db9/db25 adapters to connect the terminals

fun!

David Freitag

Heh, luckily I sit in a cube. All our stuff is industrial too which means no people either

casey

that also reminded me a co-op I did with IBM in austin in AIX product test.

which was mostly software oriented, but I did have the fun job of wiring up the test machines together, each of which had 20ish network interfaces

pulling up raised floor tiles and run bundles of cable... I don't miss that

David Freitag

5:03 PM

Yeah that doesn't sound like much fun at all

casey

I can't even recall what they had. Some tokenring, some ethernet of various speeds, fibrechannel, fddi, hippi, and who knows what else

one of my favorite memories of that job was an enclosure of 3 racks worth of 10k rpm disks

It took 2 three phase power mains and sounded like a turbine spinning up when you turned it on

derobert

5:57 PM

@Gilles the Debian tag description says its not for derivatives... what tag should be used for things that apply to Debian and derivatives? (I'd guess it should be debian, and the description needs changing). w/r/t unix.stackexchange.com/questions/147226/…

David Freitag

@casey That's crazy

Gilles

@derobert debian can mean Debian only, or Debian and its derivatives. I think that makes sense: if someone makes a derivative of Debian, there's no knowing a priori whether something about Debian will also be true for that derivative.

The only questions that don't apply to Debian derivatives are questions about the Debian project itself, and we hardly ever get those

derobert

@Gilles Ok. I'll edit the tag wiki.

Gilles

The questions that should not be tagged debian are those that apply to some Debian derivatives but not to Debian itself. But people don't spontaneously use debian for that

@strugee @jasonwryan @slm Why? (see the last handful of messages)

derobert

Ok. Edited.

Faheem Mitha

6:12 PM

@Gilles that might be pushing the debian tag. By that logic, all ubuntu questions could be tagged debian.

Actually, I think that we get a fair number of derivative specific questions.

derobert

@FaheemMitha well, if its a Ubuntu question that's actually about dpkg, I don't see a problem there...

terdon

@derobert I'm going to change the wording, most non-natives will probably be confused by pertaining (and you forgot the to).

Gilles

4 mins ago, by Gilles

The questions that should not be tagged debian are those that apply to some Debian derivatives but not to Debian itself. But people don't spontaneously use debian for that

Faheem Mitha

That don't really apply to Debian. E.g. my distribution repository is broken.

derobert

@terdon Please feel free. I did indeed forget the to.

Faheem Mitha

6:14 PM

@Gilles Ok, point taken. But I hope people will be able to keep track of the difference.

terdon

Done

> Debian is a community driven GNU/Linux distribution first announced 1993. Many other distributions are influenced or originate from it, like Ubuntu or Knoppix. Do not use this tag for questions that only concern a derivative distribution and not Debian itself. Use that distro's tag instead.

derobert

I wonder if "Use this tag for questions that apply to Debian; if the question concerns only a derivative distribution, use that distro's tag instead" would be better.

terdon

@derobert Much! Will you do it or shall I?

derobert

I'll do it

terdon

Thanks

derobert

6:17 PM

done

unix.stackexchange.com/revisions/2853/5

Hmm. Guess that doesn't onebox

> Debian is a community driven GNU/Linux distribution first announced 1993. Many other distributions are influenced or originate from it, like Ubuntu or Knoppix. Use this tag for questions that apply to Debian; if the question concerns only a derivative distribution, use that distro's tag instead.

terdon

Cool.

Braiam

2 yro question, 1 upvote, +1k views, anyone knows the answer? unix.stackexchange.com/q/19407/41104

@slm can you repro ^? or spotify now distribute a rhel package

terdon

@Braiam Damn, no, I've installed spotify from their repo and it works fine. Mostly.

Gilles

> Debian is a community-driven GNU/Linux distribution which provides a large range of packages and supports a large range of architectures. It strongly focuses on free software. It has several derivatives, notably Ubuntu and Linux Mint.

That's better

we don't need the note about not using it for Ubuntu and stuff in the excerpt, because that isn't something people do

Braiam

@terdon rhel?

terdon

6:25 PM

@Braiam Debian.

Gilles

OTOH the large number of packages and architectures are important characteristics

derobert

@Gilles That's a useless excerpt under the tag wiki guidelines, though.

@derobert why?

^ is in private beta

6:26 PM

@Gilles because its a generic definition of the term, no longer anything about how its used on our site

No one here asking a Debian question is wondering "what is Debian, anyway?"

Gilles

@derobert the excerpt should cover both aspects as needed

there's no need to define when the definition is obvious, and no need for usage guidance when that guidance is obvious

terdon

I'm with @derobert on this. That excerpt defines the obvious and offers no guidance on the non-obvious (like whether or not Qs about derivatives should be tagged with debian)

Anyone likely to use the tag will know what Debian is

Gilles

Maybe I added too much to the excerpt, but “Use this tag for questions that apply to Debian; if the question concerns only a derivative distribution, use that distro's tag instead.” is definitely not right for the excerpt, because it isn't guidance that people need

we don't have a huge influx of people using debian to mean Ubuntu

terdon

@Gilles How so? The point that makes is that the tag should not be used for Ubuntu/Mint etc questions.

Gilles

@terdon yes, but that isn't important, because people don't do that.

we don't need to tell people not to use debian to mean Red Hat either

derobert

6:29 PM

@Gilles We don't. But the previous wiki also explicitly said not to do that. So, maybe we don't have that problem because we already documented not to do that.

Or maybe it is indeed obvious enough to not need documentation... but then we should just delete the excerpt.

terdon

@Gilles Perhaps but as it stands that excerpt is basically useless. It is defining what everyone knows and gives no help on the tag itself.

Gilles

@derobert No, for the first 3½ years the wiki didn't say that, and it wasn't a problem

Faheem Mitha

Some help here, guys.

In

0

A: Sort installed applications according by usage frequency?

According to http://popcon.ubuntu.com/README This package contains a script, /usr/sbin/popularity-contest, which generates a list of the packages installed on your system, in order of most-recently-used to least-recently-used. The simplest way to use this information is to help clean u...

The '<OLD>' got messed up.

derobert

blog.stackoverflow.com/2011/03/redesigned-tags-page #2--5 all say that the when to use it is the important part, if any part is...

Faheem Mitha

Do I escape it or what?

terdon

6:31 PM

@FaheemMitha Fixed.

Faheem Mitha

@terdon Thanks.

terdon

yw

derobert

@terdon fixed better :-)

terdon

@derobert Fine use the easy and elegant way. :P

derobert

LOL

@FaheemMitha you were missing one space to make it a code block. It counts funny on quoted code blocks. Just keep adding spaces until it works...

Faheem Mitha

6:33 PM

@derobert ok, thanks.

Eww, why am I linking to ubuntu?

terdon

@FaheemMitha Wash your hands.

They have some pretty good documentation though.

derobert

I actually Googled for something the other day and found an answer on AskUbuntu. And.. it was both correct and useful!

Faheem Mitha

@derobert Which was?

terdon

@derobert There are some perfectly good answers there. And not all of them were written by @Braiam or me :)

derobert

@FaheemMitha Let me find it.

terdon

6:38 PM

A lot of good stuff about apt etc for example. Though granted, a lot of that was written by Braiam.

Faheem Mitha

@derobert ok

derobert

6

Q: Annotating packages at installation to ease maintenance with apt / aptitude

I manage my packages with aptitude. I occasionally go through my list of packages, removing obsolete applications (in the sense that I do not want to use them any more). For example, while I have a limited number of development libraries on my system that I do want installed permanently, a lot ...

apt package-management aptitude

That one.

Was tempted to flag it to move to Unix.SE, because its actually useful :-P

Faheem Mitha

Interesting. I'd not really registered that aptitude had user tags.

I think I've run into enzotib before. Can't remember where though.

Oh, he's a high rep user here. That must be it.

I wonder if SE has a "connected" app, which given two users, shows connections between them.

Like one answered or commented anothers question.

Braiam

@terdon mm?

terdon

@Braiam Trying to convince derobert that there is some good content on AU.

Faheem Mitha

6:52 PM

@terdon Along with tons of crap. But we've had that conversation already.

terdon

:)

And you well know which site I prefer.

casey

The worst thing about AU is that it is always cited as justification in proposals for distro-specific stacks that pop up on A51

"well, ubuntu has one...."

Ramesh

8:10 PM

-1

Q: using mysqlimport on a large amount of csv files in a directory via bash scripting

I have a directory with approximately 75 csv files in it that I need to mysqlimport into a MySQL database. The MySQL database does not have the tables created. The files: * The data is all numbers * All the data in the fields is less than the size of a 32-bit signed int. * The fields are all...

shell-script mysql csv

Can this be voted to close?

Abel Cheung

@Ramesh The only problem for that post is that OP doesn't show any effort on trying to solve the problem

Ramesh

Yeah. It just seems sort of problem description. I want some opinion from others as well before voting to close.

derobert

8:47 PM

unix.stackexchange.com/questions/147315/… ... I'm pretty sure the OP's understanding (or lack thereof) is beyond our ability to help.

derobert

9:06 PM

@Ramesh well, I voted to close. And just now remembered to downvote the question as well ...

mikeserv

@VolkerSiegel -

I used SIGPIPE here:

tr \\0 \\n </dev/zero | env - \
PS1='${z:+$(kill -PIPE $$)}${z0+${1-
}}$((((n=n+(i=${2-1}))-i)+${z0=0}))\
${0%%*[s${z:=${z0#$((n>${3-100}))}}]*}' \
dash -si 2>&1 -- Volker 8 36

It's mostly stupid.

But I was trying to see how far I could go with just var eval side effects.

That's basically nl or seq or some bastard of the two.

Anyway - it's all current shell, and it's done in the prompt, so I couldn't figure out how to redirect 2>&1 without a final error from the shell upon killing it.

But SIGPIPE does it softly or whatever you said.

0Volker8Volker16Volker24Volker32

casey

9:22 PM

@derobert is that even on-topic here? I think asking how to program such a tool falls outside our scope

Ramesh

@derobert thanks. I also voted to close now.

derobert

@casey Depends on if it fits within the scripting language exception. But I'm not about to migrate that question to SO.

"That's a programming question, try Stack Overflow." ... not a good idea.

mikeserv

@derobert - what I don't get about the question is why ready-made-tools and source-code are assumed to be mutually exclusive...

casey

@derobert I wouldn't migrate it, I was just considering an off-topic CV and I certainly wouldn't even suggest he re-post it there

It wouldn't last long there as a "give me some code to write a python script" Q with no work shown

derobert

10:00 PM

@casey Sure, I guess that'd be fine too. I would personally like to declare a lot of the write-a-script-for-me questions we get to be off-topic. But there doesn't seem to be consensus on that.

Though when I look in the help center, the exception is for shell scripting. Not Python. So I guess off-topic is fine.

Or it could be an off-topic request for learning materials.

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