Ask Ubuntu General Room

TheWanderer

4:00 PM

@AndroidDev really? Can't ARM64 run ARM apps?

Android Dev

@TheWanderer Possibly. But we will still need to compile it for ARMv7 and ARMv8

Nathan Osman

@AndroidDev Yeah. That's what I did with GitDroid back in the day.

It bundled the Git binary for i386, ARM, and MIPS.

(Apparently there are MIPS phones running Android. Who knew.)

Android Dev

We'll have to compile for all of those --^

Nathan Osman

I wouldn't worry about x86_64.

Android Dev

@NathanOsman Well now here's an idea.... what if we ran a hidden webview in the background and then just used a Javascript API?

Nathan Osman

4:04 PM

@AndroidDev I don't know if you can run a webview in the background.

TheWanderer

@NathanOsman what is MIPS

Nathan Osman

@GeorgetheDev what is mips?

George the Dev

MIPS

MIPS may refer to: == Technology == Million instructions per second, a measure of a computer's central processing unit performance MIPS architecture, a RISC instruction set architecture Maximum intensity projection, a volume rendering technique Multiband Imaging Photometer for Spitzer, an instrument on the Spitzer Space Telescope Multi-directional Impact Protection System, a 'slip-plane' technology inside athletic helmets designed to reduce rotational forces that can result from certain impacts Stanford MIPS, (for Microprocessor without Interlocked Pipeline Stages) a research project at Stanford...

Nathan Osman

@GeorgetheDev what is MIPS architecture?

George the Dev

MIPS architecture

MIPS is a reduced instruction set computer (RISC) instruction set architecture (ISA) developed by MIPS Technologies (formerly MIPS Computer Systems). The early MIPS architectures were 32-bit, with 64-bit versions added later. There are multiple versions of MIPS: including MIPS I, II, III, IV, and V; as well as five releases of MIPS32/64 (for 32- and 64-bit implementations, respectively). As of April 2017, the current version is MIPS32/64 Release 6. MIPS32/64 primarily differs from MIPS I–V by defining the privileged kernel mode System Control Coprocessor in addition to the user mode architecture...

Nathan Osman

4:05 PM

There.

IanC

guys, does someone here knows how to program with openssl-lib?

Nathan Osman

In C?

IanC

yeah

Nathan Osman

A little bit.

114

A: Programmatically Create X509 Certificate using OpenSSL

I realize that this is a very late (and long) answer. But considering how well this question seems to rank in search engine results, I figured it might be worth writing a decent answer for. A lot of what you will read below is borrowed from this demo and the OpenSSL docs. The code below applies ...

IanC

I was just wondering how hard it is to learn it for someone who only knows the basic structure of a SSL connection

because I had a glance of it before and looked really complicated

Nathan Osman

4:06 PM

My only experience with it is generating a self-signed cert and doing some simple signing.

Android Dev

@NathanOsman What about this? github.com/ericwlange/AndroidJSCore

And this one says it creates a webview behind the scenes: github.com/evgenyneu/js-evaluator-for-android

TheWanderer

@NathanOsman:

Nathan Osman

LinkedIn thought I might be a good fit for "Clang Frontend Compiler Engineer" at Apple.

IanC

@NathanOsman I see, guess actually making a connection would be much more complicated right? considering the many different encryption keys that can be used

TheWanderer

@NathanOsman ew

Apple and Frontend?

you?

wat

Nathan Osman

4:08 PM

Not that kind of frontend.

Clang is a compiler that uses the LLVM backend.

IanC

encryption keys I meant encryption algorithms, my bad

TheWanderer

the back frontend?

front backend?

chaskes

Never saw this before ^ . A debian logo on the error.

Nathan Osman

Sidenote: I'm really questioning why Debian had to go and use systemd. Ubuntu basically had no choice at that point.

chaskes

It was in systemd-udevd. wonder if that matters.

TheWanderer

4:11 PM

lol

Nathan Osman

@chaskes The timing of your message was... timely.

Android Dev

@NathanOsman So with the HTTP API, the Java code won't be directly calling the Go code, right? Which would mean not as big of a performance hit?

P.S That was sent from the Android app :D --^

cl-netbox

@chaskes sudo nano /etc/default/apport ... change enabled=1 to enabled=0 ... then you won't see it again ! :D :D :D seriously : mostly these warnings are faults within the acclication itself (be it with a debian or with an ubuntu logo) ! :)

chaskes

@NathanOsman lol

Nathan Osman

@AndroidDev Well, actually, the Java code uses HTTP to communicate with the Go app which connects the the chat API. So there is some overhead but not much.

chaskes

4:17 PM

@NathanOsman Then again, the odd that we would be complaining about systemd at any given time are pretty high. :)

I loaded up Devuan, btw. Debian with sysvinit.

Nathan Osman

How is it?

Android Dev

@NathanOsman Sorry for the noobness, but since I've never used Go before, how do I listen for new messages with your API? Your documentation only says "To receive events from the chat server, simply receive from the Events channel in Conn:"

cl-netbox

@chaskes chat.stackexchange.com/transcript/message/37728555#37728555 application instead of acclication of course ... typo - sorry ! :)

chaskes

Very solid version of Jessie.

Nathan Osman

@AndroidDev I'll show you an example of how that works.

for e := range conn.Events {
    // e contains a single event
}

Android Dev

4:23 PM

@NathanOsman So then I would have to check if e == 1?

Nathan Osman

No.

Since you're receiving from a channel, the loop ends when the channel is closed.

e will always be a valid event.

Android Dev

@NathanOsman So then how would I check what kind of event it is?

Nathan Osman

e.EventType

Here's the list of events: github.com/nathan-osman/go-sechat/blob/master/event.go#L10

Android Dev

@NathanOsman Remember, I've never used go before. What do I do with that?

TheWanderer

@NathanOsman so did you enjoy the red alert badge that tol you you had 2000000 notifications?

Nathan Osman

4:30 PM

@TheWanderer did not get

TheWanderer

rly

Nathan Osman

@AndroidDev You can do this:

if e.EventType == sechat.EventInvitation {
    // process invitation
}

In that example, e.RoomID contains the room the user is invited to.

You could then join the room with:

conn.Join(e.RoomID)

Android Dev

Ah, okay

Hmm, nothing's happening

for e := range c.Events {
// e is of type *Event
if e.EventType == sechat.EventMessagePosted {
fmt.Sprintf("Message posted!")
}
}

Thomas Ward

randomly appears

Android Dev

randomly disappears

Avery

4:40 PM

weird

copying files causes my cpu load to skyrocket

Nathan Osman

Does that include iowait?

Avery

it gets it from uptime

Nathan Osman

@AndroidDev That should work. Were there any messages posted in the room you joined?

Android Dev

4:53 PM

@NathanOsman Yeah; I told it to join the AU general room

Seth

https://t.co/YNfKlnC4ad

Tweeted by WholesomeMeme on May 29, 2017 at 4:01 PM

okay that's really cool.

user136984

5:06 PM

@TheWanderer @NathanOsman: What's this new app you two are working on by the way? :)

Nathan Osman

@ParanoidPanda Android app for chat.

Android Dev

@ParanoidPanda github.com/zacharee/ChatExchange

user136984

@AndroidDev: Cool name! :D

Android Dev

@NathanOsman So any ideas why it isn't detecting messages being posted?

Nathan Osman

Anything showing up in logs?

If it runs into anything abnormal, it should write stuff out to the logs.

Android Dev

5:09 PM

@NathanOsman Well, there's this

org.golang.example.android E/GoLog: time="2017-05-29T17:08:16Z" level=info msg="connected to WebSocket" connected=true context=sechat

user136984

@NathanOsman: What language are you using?

Android Dev

Java & Go

Nathan Osman

@ParanoidPanda It's an Android app, so Java.

user136984

Oh, good choice! ;D

Nathan Osman

@AndroidDev Hmm... sounds like it should be receiving events.

If you stick a fmt.Println("test") before the for{} loop, does it execute?

That will tell us if the code is even reaching the loop.

OH WAIT A MINUTE.

I found the problem.

34 mins ago, by Android Dev

for e := range c.Events {
// e is of type *Event
if e.EventType == sechat.EventMessagePosted {
fmt.Sprintf("Message posted!")
}
}

You are using Sprintf() and ignoring the return value.

...which is basically a NO-OP.

Try changing Sprintf to Println.

Android Dev

5:11 PM

I told you I don't know how to use Go :D

Nathan Osman

Sorry for not noticing that sooner.

Android Dev

What does sprintf do anyway?

@NathanOsman Uh-oh ../../hello/test.go:46: undefined: Println

Wat.

How can println be undefined?

Nathan Osman

fmt.Println

@AndroidDev It is the same as Printf but instead of writing to STDOUT, it returns the result as a string.

Android Dev

facepalm

Okay, here goes

test

Mmkay, that seemed to work

Nathan Osman

\o/

Android Dev

5:16 PM

@NathanOsman Can you post another message? I want to watch the lag time

Nathan Osman

By the way, I have more examples of using the library here: godoc.org/github.com/nathan-osman/go-sechat

Android Dev

Okay, so it lags maybe 100ms behind the webpage

Nathan Osman

@AndroidDev Should be pretty minimal since it is using the WebSocket directly.

Android Dev

@NathanOsman Now how can I print out the actual message content?

Nathan Osman

e.Content for the raw data.

e.TextContent for the content without HTML, mentions, etc.

Both are strings.

Android Dev

5:19 PM

So what's in the raw that's not in the other?

Nathan Osman

All of the HTML formatting (bold, links, etc.) and an @user that precedes the message.

Android Dev

Ah

Nathan Osman

For example, in this message:

3 mins ago, by Android Dev

@NathanOsman Now how can I print out the actual message content?

e.TextContent would be "Now how can I print out the actual message content?"

Android Dev

Uhm...

level=error msg="websocket: close 1006 (abnormal closure): unexpected EOF" context=sechat

Nathan Osman

That is both bad and good.

Bad because it means something weird happened with your connection

Good because the package is designed to reconnect after 30 seconds :D

Android Dev

5:22 PM

Huh, it seems to be working now

Yep, just got the print in AS from that message

@NathanOsman Could it be because I'm logged in on the computer and then my tablet is also logged in?

Nathan Osman

It shouldn't make a difference.

One possibility: Android might be overly aggressive in putting the device to sleep to conserve battery. This might be affecting the websocket connection.

You could grab a wakelock to prevent that.

Android Dev

@NathanOsman Thanks for the help. My next question is how can I "grab an instance" of the Go code or something so that it doesn't have to re-sign in every time I use the post message call?

Nathan Osman

The signing in shouldn't take more than 3-4 seconds and unfortunately, it happens each time the package starts.

To work around that, I'd have to store the cookies from the cookie jar that the request code is using.

And that introduces some other issues.

Android Dev

Hmmm

Nathan Osman

It really shouldn't be a problem to sign in every time.

Android Dev

5:34 PM

@NathanOsman Taking 3 seconds to post each message wouldn't be annoying?

Nathan Osman

@AndroidDev Oh, you're signing in for each request?

Android Dev

@TheWanderer --^

@NathanOsman yeah

Nathan Osman

Why not sign in and just reuse conn for every message you send?

Android Dev

Well the question is how to do that from Java

GTG; I'll be back later :)

Anwar

hi

I wanted to dupe this but the link has zero upvote and OP isn't responding. What do I do?

Nathan Osman

5:44 PM

So it's 28° C here...

ಠ_ಠ

Anwar

We had 35 C yesterday. and today was 31 C. And We're given a cyclone warning for this night

Seth

@Anwar huh, it was 30 here yesterday and tomorrow we have thunderstorms :P

Anwar

That's not very common I guess!

Same sort of weather occurring on different part of the world!

How common is thunderstorms there?

Seth

Not very common. We get them maybe once or twice a year.

TheWanderer

@NathanOsman 15 here hue

Anwar

6:01 PM

Oh! Same here. But we don't get that signal 10 very often. Maybe once per 5-6 years.

TheWanderer

@NathanOsman how is NS going

Nathan Osman

@TheWanderer macOS is still being stupid.

TheWanderer

duh

Anwar

I originally reviewed this to leave open and then saw the other question from OP that suggested that they had been able to figure out the solution. so deleted the answer and closed as no-repro here

Now, OP commented there asking about the launcher

terdon

@Anwar Why would you delete the answer?

Rinzwind

6:13 PM

deleting is a part of life

Anwar

@terdon OP's other question got an answer which was essentially better on the icon part.

terdon

OK, but why delete yours?

It had the answer about how to install the panel, after all.

Anwar

@terdon Ok, I was asking opinion. undeleted now :)

terdon

I also reopened it since it didn't seem like a dupe.

David Foerster

Hi all!

I'm learning my first poem in over 15 years.

52 verses for my grandma's 80th birthday. :-D

Anwar

6:20 PM

Hi @DavidFoerster !

David Foerster

Google is treading on Tolkien's work: go.googlesource.com/gollvm :-D

Seth

Man, IPv6 is complicated.

Nathan Osman

Yes.

Android Dev

@NathanOsman So I tried to return the instance of sechat to pass in later, but I got:

test.go:14: use of package sechat without selector

Nathan Osman

Can I see the code you're using?

Android Dev

6:34 PM

Sure, just a sec

@NathanOsman It's a bit messy since I've been trying different things, but here it is paste.ubuntu.com/24705776

Seth

@Zanna do you drink coffee?

Nathan Osman

@AndroidDev c is an instance of *sechat.Conn.

So:

func TestNathansAPI(message string, username string, pass string) sechat {

Should be:

func TestNathansAPI(message string, username string, pass string) *sechat.Conn {

Android Dev

Ah

Ok, let me try it

Nathan Osman

Same for:

func TestNathansAPI2(chatInstance sechat) string {

Change sechat to *sechat.Conn.

Zanna

@Seth only in special circumstances - I'm very sensitive to caffeine, so I actually mainly drink herbal tea. My mum loves to drink coffee with me, so when I'm home, I take about a thimble of coffee with a whole lot of coconut milk with her :)

just to be social

@DavidFoerster awesome!

what poem is it?

Seth

6:39 PM

@Zanna you should try this then teeccino.com. My mom got me to try it, and I think I will try drinking it for a bit (I don't drink coffee). It's an herbal blend designed to replace coffee.

2

Zanna

@Seth oh awesome! there's one like that here I like called Caro - it's really nice

Seth

@Zanna Oh cool!

Zanna

that stuff looks great

I'll definitely try some

thanks a lot!

Android Dev

@NathanOsman Oh great, now Android Studio says it can't resolve the method :(

Maybe I need to do a little reading on the basics of Go

Seth

@Zanna np. let me know what you think :)

Ubuntu Questions on U&L

6:49 PM

0

Q: Textfile functions in Linux

Give the instruction to search in the file “/use/share/dict/words” for words that start with “b” and end with “o” and contains an “i” or “g”. A command has to be typed in the terminal displaying a word that has the specifications as described above. I'm using Linux Ubuntu and unsure of how to do...

Android Dev

@NathanOsman Wat. Now those two methods aren't showing up, but a second hello world method I just added shows up fine.

<WAT>

If I remove the *sechat.Conn it shows up fine

</WAT>

David Foerster

@Zanna a custom adaptation of ingeb.org/Lieder/machauff.html

Zanna

@Seth will do!

Nathan Osman

@AndroidDev weirdness.

Zanna

@DavidFoerster alas, no German. But I get a gist of its loveliness from GT's mangling :)

Android Dev

6:57 PM

@NathanOsman Wait a sec, could it be because I need to specify a new object type in Java? Because Java doesn't know about any conn objects

Nathan Osman

Wait, how did Java come into this?

Android Dev

@NathanOsman Because the method is being called from Java

Nathan Osman

How are you doing that?

Android Dev

@NathanOsman github.com/golang/go/wiki/…

TheWanderer

hmm

XDA published this article xda-developers.com/…

that says at the end:

> He and I are working on a new application that will incorporate this tweak and many, many more so unrooted users can explore all the hidden tweaks available on their devices.

I commented twice, inquiring as to how similar it will be to my app, and both comments were rejected

Nathan Osman

7:01 PM

XDA is... well.

I have had problems there too.

TheWanderer

this is worrying

Nathan Osman

Dreams of being rich == poof?

TheWanderer

lol

Android Dev

@NathanOsman I'm just using Go Mobile. It lets you call Go methods from Java

Nathan Osman

That's pretty neat.

Android Dev

7:03 PM

@DavidFoerster dreams_of_being_rich.poof(true)

@NathanOsman I'm wondering if Java doesn't like it because it can't determine the return type?

David Foerster

@AndroidDev class dreams_of_being_rich { void poof( bool state = true ); }

Nathan Osman

No no no no no. This is Java. We end up with DreamsOfBeingRichDestroyerFactory.create(this).destroyMoney(true).preserveLife(‌true).build().destroy()

Yours wasn't complicated enough :P

TheWanderer

static methods, eh?

Nathan Osman

Yus.

David Foerster

@NathanOsman Pff… Java doesn't even have default method parameter values.

Nathan Osman

7:05 PM

Endless overloads FTW.

David Foerster

Instead you have to create more overloads than you have fingers and toes or use helper objects like maps or enumeration type lists.

Android Dev

@NathanOsman Wat. Java finds the method just fine if the return type is string or int, but claims it doesn't exist if the return type is *sechat.Conn

Nathan Osman

Hrm... maybe it doesn't like non-primitive return types.

David Foerster

I should stop eating ice cream

… at least for today.

Nathan Osman

Do the bindings allow goroutines to run correctly on their own?

If so, there may be a better option.

David Foerster

7:09 PM

There are still a couple of very ripe avocados, some hummus, Turkish pastes and pide.

Nathan Osman

You could use a global variable for *sechat.Conn and then just reference it in each method.

David Foerster

Sounds like I'm going to have shawarma tonight.

Android Dev

@NathanOsman How would I determine the answer to that?

@NathanOsman That was my next thought actually

Nathan Osman

@AndroidDev Apprently goroutines do work correctly.

Anwar

I think this question is too broad

David Foerster

7:15 PM

@Anwar It's pretty broad but not too broad. It's a relatively long but conclusive list of criteria to compare 3 similar things.

IanC

quick question that might be a stupid one

Zanna

hey @IanC!

IanC

hey @Zanna, long time, how have you been doing? :)

Zanna

kind of not good

getting kicked out of my flat due to landlord moving and putting it up for rent as a complete thing

work been kind of bad

running out of money

London cost of living getting worse

so luckily I can move back with my folks up in Lincolnshire, but I'm pretty stressed by the timing, I have stuff booked I will have to cancel

don't know how I will manage to get work

I'll figure it out though!

what about you?

IanC

damn, sorry to hear it, looking for a new place can be really annoying, but hopefully you'll find a nice one, maybe even better than this last

did he give you some time to look for a new place?

if things get too tight it might be a good idea to go back with your folks, take a breath before looking out for something again, much harder to look for a place with a deadline :/

Zanna

7:22 PM

yeah but I'm not going to, just going to leave town, I am so tired of flatsharing and can't afford anything else - staying with my folks for a while

oops, kind of venting, sorry!

what were you going to ask originally?!

IanC

well, think it might be a good idea for a while then, sharing a place can be tiring if you don't find the right people to share with, and sometimes that's a bit hard

are your folks place much far from London? Have no idea of distances there in UK :p

@Zanna oh, don't worry, it was nothing that important, I was just following those steps to verify an iso download, and was wondering why it asks you to run gpg --verify SHA256SUM.gpg SHA256SUM when the latter seems to be just a text file with no signature

Zanna

3 hours door to door. Not commuting distance but not too bad. Trains cost £70 on the day though O.O

@IanC I find anything with gpg confusing!

IanC

wow, that's some expensive ticket! Even more if I convert it to my currency haha

@Zanna I know right? I kind of get how it works, overall, but when running the commands there's always some small detail that gives me some doubt, and I get confused with the ring of trust too!

David Foerster

@IanC Train travel isn't priced competitively with air travel in Europe. The only good thing about the former is that there are far more train stations than airports.

Zanna

oh yes I remember that in Brazil it cost about the same to get a flight as to get a bus

David Foerster

7:32 PM

…and it's often less of a hassle because you don't need to take care of airport transfers, security and check-in.

IanC

yeah, sometimes it's even cheaper to get a plane here than to get a bus

and we basically don't have trains that transport people

David Foerster

Many weekly commuters (at least in Germany) prefer to travel by train between large cities in the north and south even if there are suitable airports on both ends.

IanC

has to do with being able to enjoy the view during the trip? :p

David Foerster

It's more comfortable and takes about the same time if you take airport transit and check-in into account.

Also, especially business travellers would rather sit 4 h in a train and read or work on a laptop in the mean time than ride 1 h to the airport, walk around and wait in queues for ½ h, squeeze into a relatively small aeroplane seat for ½ h and ride back into the city for another hour.

Zanna

probably has a lower carbon impact too

I get all my reading done while commuting :)

David Foerster

7:40 PM

O.O I printed something at a copy shop yesterday and now my USB drive has a Windows virus.

That drive hasn't been connected to a Windows machine in months.

virustotal.com/de/file/… and virustotal.com/de/file/…

I guess I need to write them an e-mail.

Seth

wow

IanC

@DavidFoerster not sure that will help much, considering they plug tons of strangers USBs per day on that computer :p

David Foerster

@IanC Yeah, but they should still disable autostart, update their software against vulnerabilities and now also purge their system from the virus.

Android Dev

@NathanOsman I hope I'm not annoying you, but I got this when I tried to make the Conn object global:

hello.go:31: cannot assign error to err (type *sechat.Conn) in multiple assignment

user136984

@DavidFoerster: Can't you even buy special devices to plug your USB through in order to not allow firmware infections to get on your system?

IanC

7:47 PM

@DavidFoerster they should, just don't think it's likely they will :/

no reason why you can't send them an email though

Nathan Osman

@AndroidDev Ah, the multiple assignement error.

That means you need to switch from := to = and declare err ahead of the line.

var err error

...ought to do the trick.

badp

var rgarbl;

Nathan Osman

wat

David Foerster

@ParanoidPanda You can buy external drives that have a switch to disable write operations. There are also USB mass storage controllers that you can plug in as a proxy to filter out any write commands (often used in forensics).

Nathan Osman

WHAT THE HECK MACOS. I'VE GIVEN WORLD READ PERMISSION TO THIS FILE. Y U NO LET OTHER USERS cat THE FILE?!?!

macOS really is annoying.

Android Dev

7:52 PM

That fixed the compile error :)

Now let's see if it works

user136984

@DavidFoerster: Yes, well, then they could use one of those as well as a good AV, maybe Linux and a VM or at least a community that is secured properly against most infections.

Android Dev

@NathanOsman I spoke too soon :(

hello.go:77: c.EventMessagePosted undefined (type *sechat.Conn has no field or method EventMessagePosted)

Nathan Osman

@AndroidDev you want sechat.EventMessagePosted.

It's not part of the connection.

badp

David Foerster

@NathanOsman Maybe they have a security model similar to Microsoft where "everyone" means everyone with a valid user account and "anonymous" means everyone even without a user account.

Nathan Osman

7:54 PM

$ stat cert.pem
16777217 2172651 -rw-r--r--

That should grant everyone read permission.

And yet:

$ cat cert.pem
cat: cert.pem: Permission denied

Oh. Hehehe.

Grins sheepishly.

3

The directory doesn't have read permission.

badp

var rgarbl;

Nathan Osman

Backs away from the computer slowly.

5

Android Dev

@NathanOsman And now the for loop runs through instantly :( Gah!

Nathan Osman

Instantly?

Android Dev

Wait a sec, do I have to create a new instance of the class? I'm just calling it directly ATM

David Foerster

7:58 PM

Anyway that makes me think I should probably get a write-protectable USB drive for stuff like this.

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