/dev/chat

2:50 AM

Does anyone happen to know why mime attachments show up as significantly larger (at least in Alpine) than the actual files that are being attached?

casey

3:50 AM

@FaheemMitha base64 encoding

iirc that adds about 33% overhead

Faheem Mitha

7:57 AM

@casey Thank you. I don't see why that is necessary, but what do I know.

AppAraat

8:52 AM

Hello, I have a question not necessarily related about UNIX & Linux. I wanted to ask this on the Meta SE, but I don't have enough reputation there.

In any case, I want to search special characters. For example, on the vi(m) SE, if I search for "C-c" it also gives results of C/C++ instead of only C-c.

There's this question - http://meta.stackexchange.com/questions/258975/how-to-search-for-literal-special-characters - but it doesn't really answer that.

So what should I do? Should I ask a question on the Meta SE?

Archemar

@AppAraat I fail to underrstand your question, C is lexically included in C++

AppAraat

@Archemar Sorry, English is not my native language.

Suppose I want to search exactly for "C-c" and only get results that contain the string "C-c" (case sensitivity is not really important for the sake of the example). How do I do that without getting results which also contain the string "C/C++" or "C, C++, C#" etc. ?

Archemar

9:14 AM

best I come with is "C-c" in search field (9 return agains hundreds), yet still catching C\C++

AppAraat

I think the "-" character is simply getting ignored. I wish there was a method of escaping special characters.

Archemar

I also tried "C\-c", same result

AppAraat

So if I want to ask a question regarding this, what should I do? Do I post an answer to that Meta SE question I linked? Or make a new question? I can't add comments yet with my reputation I think.

Archemar

9:36 AM

This is not the same question, I think you may ask a new question.

Faheem Mitha

@Archemar It's not clear what you are asking. Search where exactly? Are you searching files?

Archemar

we try to search the string "C-c" Upper-C, minus sign, lower C in vim.SE, but result only (mostly) bring C/C++ Question/Answer, so I suggest @AppAraat to ask on meta.

Faheem Mitha

Sorry, the above should have been addressed to @AppAraat.

AppAraat

11:09 AM

@FaheemMitha Basically what @Archemar said. I'm working on a question now. I've found this question (http://meta.stackexchange.com/questions/38968/how-to-search-for-special-characters-on-stack-overflow) and one of its answers links to http://meta.stackexchange.com/questions/160100/a-new-search-engine-for-stack-exchange

I've also tried to search the http://symbolhound.com/ link but it tells me there are 0 results.

Funny enough one of their examples doesn't yield any results - stackoverflow.com/search?q=%22%2a=%22

StackExchange is pretty cool. I feel like a detective every time I'm about to ask a question.

(and of course do the necessary research to ask the question)

Also... I'm further unsure where to post the question: on the Meta SE or meta.vi.stackexchange.com

Faheem Mitha

11:33 AM

@AppAraat Ask in chat.

terdon

@AppAraat try symbolhound.com

AppAraat

@FaheemMitha chat of what?

@terdon see my previous reply, I've already tried it :)

terdon

Ah, sorry

As for where to post, the search is the same for all sites so meta.se is probably the best.

But symbolhound seems to work perfectly with "C-c" : symbolhound.com/?q=+%22C-c%22+

AppAraat

@terdon oh in that case I was searching wrong on symbolhound, this was my query - symbolhound.com/…

terdon

@AppAraat Maybe there just isn't any mention of C-c on Vi and Vim.

Is that even vi-speak? That looks like Emacs style to me.

AppAraat

11:43 AM

@terdon C-c in vi(m) stands for Ctrl+c

terdon

@AppAraat Yes, in emacs as well, I just thought that you weird vi people would have a different notation.

:P

AppAraat

I guess we just keep it compatible so the emacs people don't lose their minds :p

terdon

@AppAraat it looks like there actually aren't any posts with C-c on Vi and Vim. I tried by using the exclude search directive and still got nothing: vi.stackexchange.com/search?q=%22C-c%22+exclude%3A%22C%2FC%22

AppAraat

@terdon you mean these posts don't pop up?
http://vi.stackexchange.com/questions/300/other-ways-to-exit-insert-mode-besides-escape/1883#1883

terdon

@AppAraat Of course not, they don't mention C-c anywhere.

They have <kbd>C</kbd>-<kbd>c</kbd> you can't expect the search to parse that .

AppAraat

11:49 AM

@terdon oh sorry, I think I linked to the wrong post. But the "C-c" should be there somewhere in that whole thread, right?

terdon

@AppAraat It is, but inside keyboard tags, not as a simple C-c

AppAraat

oh I see

terdon

Ah, no, I stand corrected, there's also a <C-c>

Oh well, the SE search is basically awful.

Faheem Mitha

@AppAraat chat of whatever site it is.

That's what I do, anyway.

AppAraat

@terdon Really? I think it's pretty extensive, this must be an exceptional case or something.

@FaheemMitha that would be problematic considering I don't have 20 rep there yet.

terdon

11:51 AM

@AppAraat No, it's very well known for being pretty bad.

It's not an easy problem and they're doing the best they can but it just isn't very good at all.

Faheem Mitha

@AppAraat Oh. Well, someone else could ask on your behalf.

@terdon They need to kidnap some Google people and hold them to ransom.

terdon

Yeah

@AppAraat If you have 20 rep on any site, you can chat on any site on the network. Network rep is shared.

That's
why
I
have
>100k
rep

Faheem Mitha

@terdon Oh, yes. That's true.

AppAraat

weird, I could have sworn that it asked me for 20 rep. Lemme see if I can chat in Meta SE chat.

terdon

@AppAraat Ah, no, not there :)

AppAraat

11:58 AM

lol another exception :p

Faheem Mitha

@terdon is meta SE chat special?

terdon

Everywhere except there. There are two sets of chatservers: chat.stackexchange.com and chat.meta.stackexchange.com. You can chat on any rooms of the former, the latter is separate.

Faheem Mitha

@terdon I didn't know that. Why is that the case?

terdon

I don't really know. Load balancing? Separating the mods (all mods are also chat mods on chat.stackexchange but not on chat.meta...)?

AppAraat

I think they've changed their search engine as well. See this post for example - http://meta.stackexchange.com/questions/160100/a-new-search-engine-for-stack-exchange - therein an example is given:

"Quoted phrases are exact matches except for case-sensitivity, for example, you can search for code or symbols."

The second example (http://stackoverflow.com/search?q=%22%2a=%22) leads to 0 results.

terdon

12:08 PM

@AppAraat Yeah, that comes under the general heading of "SE search sucks"

AppAraat

12:32 PM

@terdon that's indeed unfortunate.
I made a post on Meta SE - http://meta.stackexchange.com/questions/267937/how-can-i-search-for-special-characters - but I'm not sure if I provided enough information or that it's formatted properly.
I'd love to receive some feedback on it :)

terdon

@AppAraat Looks good. You might improve it by giving a specific example of a post that contains the characters you want to find but is not in the search results.

AppAraat

@terdon oh good idea, I'll do just that, thanks!

casey

1:25 PM

@FaheemMitha email isn't binary friendly. The purpose of encoding (either old uuencode or MIME base64) is to encode binary content into the low ASCII printable character set. That introduces overhead (24 bits are each encoded as 4 characters)

Faheem Mitha

2:31 PM

@casey Not binary friendly? Why not? Corruption issues?

casey

@FaheemMitha historically it is a 7-bit text protocol that speaks plain english

and if you couldn't guarantee high ascii (128-255) will make it through the pipe, that rules out straight binary transfers

Faheem Mitha

2:48 PM

@casey Can you elaborate on "make it through the pipe"?

Oh, you mean there is no way to transfer it via the protocol?

casey

@FaheemMitha imagine your email passing through a link that only supports 7 bit characters. sending an 8-bit stream through will completely corrupt it.

these days I don't know that it as much of an issue, but I don't think you can guarantee it isn't either.

SMTP dates back to 1982 and was designed for textual content

it seems that yes, current MTA can handle 8 bit MIME encoding and 8 bit header/body text, but they can also convert to 7 bit encoding if the next mail exchanger in the link cannot support 8 bit encoding.

Faheem Mitha

3:21 PM

@casey I see.

@casey I wonder how often that actually happens.

Anonymous

3:52 PM

Hello all.

Anonymous

I recently imploded RVM and removed files relating to it. However, when I do locate rvm some stuff still remains. This happens in both root and user. Any suggestions?

terdon

@HunterStevens The locate tool uses a database and that's only refreshed periodically. On reboot on most systems, I think. Run sudo updatedb to refresh it manually.

@schily I see you found it :)

schily

yes, but I am currently in the POSIX standard teleconference and thus not fuly available

terdon

4:10 PM

No worries. Most of us tend to lurk here anyway.

Faheem Mitha

@terdon The database update runs as a daily cron job.

Customarily as user nobody, I think.

terdon

@FaheemMitha Depends on the distro I guess.

Faheem Mitha

@terdon What does?

terdon

Whether it's daily or not. You're quite right about Debian anyway:

$ grep -R updatedb /etc/cron*
/etc/cron.daily/mlocate:[ -x /usr/bin/updatedb.mlocate ] || exit 0
/etc/cron.daily/mlocate:flock --nonblock /run/mlocate.daily.lock $IONICE /usr/bin/updatedb.mlocate

Faheem Mitha

@terdon Oh, I think that's pretty standard. Find me a distribution that doesn't do that.

terdon

4:22 PM

@FaheemMitha I have no idea, hence the I guess.

It certainly makes sense to have it daily, no argument there.

Faheem Mitha

@terdon ok

I'd be surprised if anyone doesn't run it daily.

schily

4:34 PM

@terdon what is wrong with giving an answer that is sufficient for the current question and ask for more information in order to be able to enhance the answer later on?

terdon

4:57 PM

@schily Nothing, really. However, your post wasn't answering anything. You were only explaining why you asked for mntab.

schily

I was anwering that the file /etc/mnttab is most likely out of sync with the kernel and thus df could do unexpected things

Faheem Mitha

What's an easy way to annotate a JPEG, say with an arrow? I know non-easy ways.

derobert

6:00 PM

@CodeMed you need to use that syntax we used the other day to set the IP on the bridge...

We finally found the right syntax, on like the third try.

CodeMed

9:03 PM

@derobert I reviewed the chat logs, and I think this is what you are talking about:

# nmcli connection modify bridge-br0 ipv4.method manual ipv4.addresses 10.0.0.8/24 ipv4.gateway 10.0.0.1
# nmcli con down bridge-br0; nmcli con up bridge-br0
# nmcli con up bridge-slave-eno1
//i can ping from devbox to server host over network now.
# ip link ls
# bcrtl addif br0 vnet3 (where vnet3 was in results of preceding command)
//i can ping the vm from the devbox now

I just do not know how to apply it to the current circumstances.

derobert

@CodeMed well, in the previous case the connection name was bridge-br0 ... now it's Wired connection 1

(which has to be quoted as 'Wired connection 1' to protect it from the shell. Of course any of the other shell quoting methods will work, too.)

CodeMed

@derobert Things have changed slightly as I have been ripping things out and replacing all day

CodeMed's Woes

derobert

ok... don't have time to read all of that... but that's the current way to edit a connection's IP address using nmcli.

CodeMed

@derobert so do i work on modifying these commands to run on each GUEST? or on the HOST?

derobert

IP address for the guest is set on the guest.

CodeMed

9:22 PM

@derobert I collected data from the HOST and from the GUEST and then took a stab at modifying the commands that worked last time so they can work in this context. But I have questions about some of the changes/variables. Can you please review and suggest?

Data from the HOST:
[root@localhost ~]# nmcli con show
NAME UUID TYPE DEVICE
vnet2 2997cf2d-4736-4c6d-8d54-8e9fe2150399 generic vnet2
bridge-br1 8b9fd6d9-bcb4-4e1c-85ab-55905d08667e bridge --

derobert

you just need the modify to change the IP address on the guest, and the down and up to apply it. You don't need any of the bridge stuff, because the bridge isn't on the guest... it's done by those host. And shouldn't really need configuring there, beyond what creating it and adding interfaces to it in virsh already did

CodeMed

@derobert So are you saying not to run nmcli con up bridge-slave-eno1 or bcrtl addif br0 vnet3? These two commands are where the three wrongly-named variables are.

derobert

those were required to set up the bridge on your host to your LAN, a connection you also want the host speaking on

since you don't want that here, you don't need them

well, and the brctl was to fix the bridge not being started when you started the VM

anyway, I'm off again...

CodeMed

9:57 PM

Is someone willing to help with a much narrower question that is roadblocking me? I put it in a separate question:

0

Q: how do I attach devices to connections using nmcli?

An installation of CentOS 7 has two connections and three devices. How can I attach the device ens7 to the connection my-bridge? And how can I attach the device eth0 to the connection my-eth1? Here is the relevant data from the terminal: [root@localhost ~]# nmcli con show NAME UUID ...

CodeMed

10:27 PM

i think it starts with:

nmcli edit my-bridge

nmcli> goto ...

that is,

nmcli connection edit my-bridge

[root@localhost network-scripts]# nmcli connection modify id my-bridge ens7
Error: value for 'ens7' is missing.
[root@localhost network-scripts]#

CodeMed

11:11 PM

The problem might have to do with the connections being created with this syntax:

# nmcli con add con-name my-bridge ifname eth1 type ethernet ip4 10.1.1.2/24
# nmcli connection modify my-bridge ipv4.method manual ipv4.addresses 10.1.1.1/24

CodeMed

11:22 PM

@derobert I know you are slammed, but before the end of your workday, would you be willing to take a look at this? I cannot implement your suggestions until the connections are attached to a device. I should be working at my computer for several more hours.

CodeMed's Woes

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