Word for a person who likes to hang out in cafes

Question: I'm looking for a word equivalent to "barfly" applying to people who like to spend time lingering and socializing in cafes next to a coffee or a beer. It can be a slang term or something historical.
Comment: What is the purpose of the socializing? Hooking up, or just hanging out?
Comment: hanging out, "wasting time"
Comment: I was thinking some analog to *beatnik*, but I can't find one.
Comment: I don't think there's a word or expression for this... but there darn well should be! Mmm, what about froth-fly? Saucer-jockey? Espressonist? Lattetudinarian? Café lizard? Beanholer? Teatarrier? Starbucist?
Answer: I can not think of a single word in English, but we typically just call these people café-goers because they go to the café. Wiktionary1 is the only dictionary which directly attests this as a word, which it defines as "One who goes to a café". This gives somebody some room to be doubtful, but the more reputable dictionaries show that goer is applied as a  sort of suffix with the following examples:

churchgoer 2
filmgoer 3
clubgoer 4
beachgoer 4

Granted, I do not expect there to be many more examples of such words, and cafe-goer is the very rarest of them on this Google nGrams chart comparing the various goers with barfly:

However, various words using the goer suffix are used about as often as barfly, and even the small sample still consists of dozens of readily accessible printed quotations. I also sometimes heard it in news reports to name the customers of establishments such as Starbucks. Take the Forbes article China's Coffee Culture which was written by Maura Elizabeth Cunningham and published on April 28th, 2010 for example:

Aside from one caffeine-dependent American student, most of the other cafe-goers fell into three general categories. There were often tables of middle-aged Chinese women chatting over coffee and pastries, especially in the late morning and early afternoon. Businessmen also held meetings at some coffee shops, though on more than one occasion I saw their frustration at the strict no-smoking policies in places like Starbucks and Costa Coffee. The third group was composed of young couples, who would often get comfortable on the cafe's couches, nurse drinks and watch DVDs on a laptop together.

 Aside from being a respectable source, its usage here is used to preface the sorts cafe-goers in a manner similar enough to how I might expect barfly to preface the various sorts of more infamous patrons who might visit a bar, although I can not exactly find a good example for comparison at the moment.

1 Wiktionary licenses the excerpted text under CC-BY-SA 3.0 terms.
2 Collins English Dictionary—Complete and Unabridged, 12th Edition s.v., goer
3 Random House Kerenerman Webster's Dictionary (© 2010) s.v., goer
4 The American Heritage Dictionary 5th Edition, s.v., goer
Answer: I don't think that there is a (British) English word. The French have at least two words that might be relevant (and both can be seen in English texts - a sign that I might be right about the absence of an English word): flaneur or boulevardier. I know that literally they both imply movement but only from one bar to another, and that at a slow pace.
Answer: café habitué
It's cited by Merriam-Webster

a person who may be regularly found in or at a particular place or kind of place

From Google Books the following excerpt

For the cost of a drink, a café habitué can tarry in a state of detached involvement, enjoying a succession of small encounters (with people, things, thoughts) that need never be registered, acknowledged or remembered, in a space that does not compromise on homely comforts. (Teresa Gómez Reus)
Answer: Vienna: a different time, a different culture, and certainly a different coffeehouse, but still worth a look:

Im Kaffeehaus sitzen Leute, die alleine sein wollen, aber dazu Gesellschaft brauchen.
People sit in a coffeehouse who want to be alone but who need company to do so.
Seit zehn Jahren saßen die zwei jeden Tag stundenlang im Kaffeehaus. Das ist eine gute Ehe! Nein, ein gutes Kaffeehaus.
"For hours everyday for the last ten years those two have sat in the coffeehouse. That's a good marriage!" "No, a good coffeehouse."
     —   Alfred Polgar, Austrian author, 1873–1955.

There isn't a Viennese word for someone who frequents coffeehouses because even if they rarely or never go to one, the Viennese understand it as an integral part of their culture.
As for a word in English, I'd vote for café aficionado/a because it sounds like a pretentious bistro in some mid-sized American city.
Comment: And the word for people who visit or spend time at cafés is....?
Answer: How about members, or afficionados of, 'café society'?
It is difficult to find words for the individual activity of 'café-going'—yet easier to find words for what goes on there—the exchange of artistic and creative ideas, philosophising—even, coming up with new schools of thought there—as in the existentialists and Jean Paul Sartre—who famously hung-out in cafés, according to the Washington Post Op. article:
At the Existentialist Cafe': Hanging out with Sartre, Camus, de Beauvoir and More,
by  Heller McAlpin (Mar. 25th 2016).
So how about 'literati', 'café society' or 'On the Café scene…'?
On a more mundane note, what about 'coffee lovers', or 'caffeine lovers, looking for their next fix…'?
Coffee-bean lovers as in:
'Lovers of the mood-altering effects of the humble coffee bean…'
Bohemian?
Starbucks members?
Caffeine addicts?
Caffeine worshippers?
Coffee-drinkers?
☕
Comment: "Coffee lovers" are people who love coffee and drinking It, they don't necessarily go to cafés or coffee shops. "Caffeine addicts" has more negative connotations than positive. "Caffeine worshipper"  doesn't mean someone who frequents coffee bars.
Comment: The asker has not specified that she wants a 'positive term' - nor has she said how she wants to use the term - which is why I provided some different ideas.  She also said she is 'looking for an expression like 'barfly'' - which is not a particularly positive term.
Comment: S/he hasn't specified much, really. Which is why the answer is a poor fit.
Comment: How can you say 'it's a poor fit' at the same time as decrying  the question as unspecified'?  How do you know 'it's a poor fit'? You don't. That's like complaining that 'it's bad that my size 18 shirt doesn't fit my size 8 body' when all you asked for, was 'a shirt'. Why don't you ask the questioner to be more specific, instead of criticising my potentially helpful answer?
Comment: I'm glad you love tea, Mari-Lou! In the absence of many words to describe 'café-going' apart from 'café-goer' which is not a very evocative term, and which I don't think captures much of the whole 'café scene' experience, which I mentioned in my answer as a member of 'café society', I offered some additional expressions that I thought might suit the needs of the asker - or help get their mind moving on other tracks - which might help them find an answer. Caffeine addict and coffee worshipper does not per se mean that a person hangs around in cafés - but it could allude to that.
Answer:
intelligentsia (n.) - intellectuals who form an artistic, social, or political vanguard or elite

is a very common name for coffee shops and the people who frequent them.
More archaic is gad (v.), to go around from one place to another, in the pursuit of pleasure or entertainment. I suppose you could call someone like that a gadder, but to gad about sounds better.
Answer: I call myself a  "Cafe Cat", I made it up myself. Cats hang around and they interact when they want to or they can completely ignore you. They have their own agenda for whatever their doing. It's not negative in any way such as a "barfly" or a "gym rat". Which indicates  someone who's more of an annoyance. Cats are usually liked by most people, people who go to Cafe are usually very social on some level. With cats,  it's completely acceptable to be ignored by them. In fact being ignored by them doesn't make anyone hate them. it just makes it, it. People in cafes are kind of like that too. You can be ignored by them they can interact with you and if you interrupt them, they'll either love it or you'll know they don't want it. "Cafe Cat" also has a slight spin on the whole "Beatnik"  thing because back in the day they were called Cool Cats". So I votr for Cafe Cat. It's what I call myself and I think it fits.....Jen Parsley-Kellenbarger~cafe cat~coffee/cafe lover~Central Coast of California dweller.☕      4/3/18
Comment: Welcome to ELU, please consider adding sources indicating the word being used by others.


Factor scale as a dependent variable in repeated measures ANOVA

Question: I have to analyse data from an experiment in which participants performed two tasks. Each task had a different content and also a different "space condition". Content, space condition and order of presentation of content and condition were counter-balanced between participants. When participant finished the tasks, they answered a questionnaire about the difficulty of each one, containing a set of 18 questions (for each task).
I ran a factor analysis for the 18 questions referred to task with space condition 1, showing that there was just a single component, and another factor analysis with the questions related to space condition 2, that also resulted in only a single component.
My question is:
 Is it correct for me to run a repeated measures ANOVA comparing the two resulting factor scales (DV) as within subject IV ("space condition"), and with "combination of content and space condition" as between subjects IV?
Thank you for your help.
Answer: Factor analysis (FA) of your questionnaire tells you whether the questionnaire measures more than one thing. For example, a questionnaire on happiness might reveal a factor on job satisfaction and one on happiness of personal life
Comparing the output of the two FAs would tell you whether the questionnaire's structure is different under the two different conditions. If that were the case, the questionnaire would measure different things under different conditions and would be useless to you to compare your subjects' reactions to the two conditions. But I doubt you can do a meaningful factor analysis with just 18 subjects.
For self-created questionnaires you can either treat each item as a DV or the average of a subject's response over all items of the questionnaire.
I'm afraid, I'm not expert enough to answer the more pressing part of your question as to how to structure the analysis itself. Looking for the repeated-measures tag should find you some more answers.
Comment: Tank you for your answer, ThomasH. I leave the question open just to see if anyone can address the rest of the question.


How big a hole do I have to drill in concrete to embed rebar in it?

Question: I have a concrete patio that I'd like to use as the foundation for a CMU wall. I'd like the CMUs to be tied into the patio slab with rebar. I get that the gist is to drill a hole in the slab, put rebar in the hole, and then fill it in with concrete to anchor the rebar into the hole. What size rebar should I use, and how big a hole do I need to drill? If I use 1/2" rebar, can the hole be 5/8"? 3/4"? Does it have to be 1"? etc.
Comment: Nope. This is why plans and permits and inspection are required in many places. Typical method is epoxy. It requires technical rigor. It won't turn a patio slab into a foundation, however.
Comment: Often patio slabs are  not constructed suitably to serve as a foundation. To be effective as reinforcing rebar must be monolithically  bonded to the concrete. Simply sticking it in a hole will not achieve this irrespective of hole size.
Comment: Not even pouring concrete in the hole to hold the rebar to the slab?
Comment: Gotcha. Guess I won't do that.
Comment: Is your patio an add on or under the main part of the roof, like a lanai? If a lanai, the perimeter might have thick enough concrete to serve as a foundation.
Answer: I have been working with and around concrete for 20 years now. One thing is you cannot put cmu block or any other stucture on just a thin concrete pad. You must have a load bearing surface (footer) , and the specs will vary depending on soil type, frost line, and load. Second, if you wanted to dowel in to concrete you must use epoxy to anchor them. If using #4 rebar, i would go slightly larger on the bit (5/8") to allow enough epoxy for bonding and an easier initial fit.
Answer: I happened upon this as I was shopping for a new rotary hammer bit.  A couple of the posts here are correct.  If you intend to construct a wall, the foundation component that will bear the load of such a wall will have to be designed to be up to the task.  Furthermore, if you're tying into another concrete component -- like a footing or a reinforced concrete wall -- you must use a bit that allows for the placement of the rebar and the anchoring epoxy.  As a mason and a builder, I've used 5/8" rotary hammer drill bits to epoxy #4 rebar to reinforced concrete as a "tie in" or an anchor.  in general, it's been my experience that drilling the hole, blowing it out with compressed air and inserting a round "pipe" brush into the hole to loosen the concrete dust and debris is essential for proper bonding of the anchoring epoxy.  To clarify, the round pipe brush is mounted to a cordless drill and used with compressed air, repeatedly, until the hole is dust free.  Once you see no more concrete dust being forced out of the hole with the compressed air, you're ready to pump the anchoring adhesive into the hole.  We generally fill said holes roughly 1/3rd full, using a caulking gun, before inserting the rebar into the hole in a rotating fashion.  Any excess that comes out upon insertion of the rebar is simply wiped flat with a putty knife and a paper towel (to clean the putty knife).  >> Caution, if the anchoring epoxy isn't coming out of the hole during insertion of the rebar, quickly pull the rebar out and add more anchoring epoxy.  You must have the appropriate amount of anchoring adhesive to ensure a strong bond between the steel rebar and the reinforced concrete.  Bear in mind that the epoxy is beginning to set/harden as soon as it's mixed in the application nozzle, so speed is of the essence when doing this type of work.
Comment: Great first answer, welcome to Home Improvement! There's a [tour] you can take to get a little more familiar with DIY.SE. Please keep sharing your expertise!
Answer: It's been a long while since I worked construction, but I think I remember dowelling into concrete in a similar manner with a 1/2" drill bit and #4 rebar. We used a sledgehammer to drive the rebar pegs in. It MAY have been a larger bit, but I think I remember it being the same size.
Comment: For the record, this was for adding an extra few inches width to the foundation for a brick shelf, when the home buyer decided they wanted brick instead of siding after the foundation had already been poured. So the extra foundation was poured beside the existing slab, with the rebar pegs tying the two together.


Make tools indestructible in Minecraft

Question: In Minecraft, is there any way to make tools indestructible (without using mods)? I want to make some tools indestructible (for an adventure map). Is it possible to do this using enchantments (or a command of some kind?)
Answer: You can use "Unbreakable" NBT tag to make your items unbreakable. Example with a sword:
/give @a minecraft:diamond_sword 1 0 {Unbreakable:1}
Comment: This is exactly what the Unbreakable tag is for. One of these should become the accepted answer (or voted up).
Answer: Items in Minecraft have a Damage value attached to them. For tools this is used to determine how much the item is damaged. For example, diamond tools break when this number reaches 1562 (their durability).
By casting an Unbreaking III enchantment on the tool (/enchant playername 24 3) you make it last 4 times as long: 1562·(1+3) = 6248 uses on average. The game doesn't let you enchant for a higher level.
If that's not enough for you, you will have to use an external game data editing program.
Note that the program is only needed once. No mods will be required afterwards, neither for you, nor for the players of your map.
At first, make sure you have the desired tool (with Unbreaking already) in your Minecraft inventory, then close the world.
Now is a good time to make a backup of your world in case something goes wrong.
Let's use NBTEdit to edit the information about the tool.

Open the level.dat file inside your world's directory.

Go to Data → Player → Inventory.

Select the entry which has the id of your tool (for example, a diamond pickaxe is 278).

Double-click on Damage and change the value to -32768 (-2^15, the smallest number short int data type can hold).

Open the item's tag → ench → "2 entries" and change the lvl to 10. (You can make the level even larger, but it won't look good in the game: "Unbreaking X" vs "Unbreaking enchantment.level.11").

Save the file.

Now you have an item with (32768+1562)·(1+10) = 377630 uses. Moreover, for the first 360448 uses (i.e. forever) the item won't have its damage bar displayed. Also, the tool doesn't even have to be diamond: a wooden tool will still have (32768+60)·(1+10) = 361108 uses.
Comment: This does work, and the minimum damage value is -32768.
Answer: The closest you can get to that is enchanting your tools to make them last longer, increasing the uses significantly.
Another option for an adventure map would be to provide anvils through the map and hide raw materials that you could use to repair your tools.
Comment: +1. Slap Unbreaking X on it and for all intents and purposes it'll be indestructible. Well, unless it's incinerated.
Comment: @lunboks Is it really possible to give an item infinite durability using the "Unbreaking X" enchantment? If so, how?
Comment: @AndersonGreen Well, no. It'll just last a very, very long time. Unbreaking I is double durability, II is triple, III is quadruple, etc. If we're talking about a wooden tool, you could also crank up the enchantment level to Unbreaking C. That should be long enough for everyone.
Comment: @lunboks I've pulverized through unbreaking 100 on diamond tools on prison servers... just saying
Answer: You can simply do this command (in a command bock). Copy as so into game anything in the ().  It's your choice in what you want to put. Note I did this in 1.7.2:
/give @p diamond_sword {Unbreakable:1,ench:[{id:(enchantment id),lvl:(enchantment power),display:{Name:"(name of item)",Lore:["(a little msg about anything)"]}}
You can extend things like the total enchants and lines of Lore some examples
multiple enchants: ench:[{id:(enchantment id),lvl:(enchantment power)},{id:(enchantment id),lvl:(enchantment power)},{ and so on.
More lore lines: Lore:["(a little msg about anything)","Lore:["(a little msg about anything)"," and so on.
Answer: /give @a minecraft:diamond_sword 1 0 {Unbreakable:1}

Completely works. I tested it with a  gold sword in 1.8.1 and it never lost any durability.
Answer: If anyone is interested and need an indestructible item for Minecraft 1.2.5 and/or maybe for some Minecraft with SPC installed, try this: /item "number item" 1 -3000
Answer: You can use command blocks: lets say 247 is a wooden sword (247 is not really a wooden sword, just an example), so do:
give [playername or @p or something] [item ID] [amount] [191918]
so it should look something like that:
give @p 247 1 191918
That will give you an indestructible sword!
Comment: Why use a command block instead of just a command? Why use exactly "191918"?

Make tools indestructible in Minecraft


Is there any other way that we can take auto backup in oracle 11g apart from RMAN?

Question: I have tried with RMAN. But is there any other possible way that we can backup database and tables. backup using queries or stored procedures is possible?
Comment: What problem do you have with RMAN exactly? Why are you looking for something else than the standard backup tool to do backups?
Comment: No I am just looking for any possible methods that i can try
Comment: Stop "looking for any possible methods that you can try" and use RMAN - that is the tool for the job and the only answer.
Answer: The only correct way to back up an Oracle database is to use RMAN. There are alternatives but they are not as reliable as RMAN.
RMAN has a ton of features and this might make it look complicated. But in fact it's not difficult and should always be the choice to back up a database.
RMAN does not do logical backups like tables, indexes, procedures. RMAN does physical backups which means that it backs up the datafiles block wise. It does not care what is inside this block.
I think there are a lot of beginner tutorials on the internet. I personally like the descriptions on http://oracle-base.com/.
To automatically back up a database use the operating system scheduler and run a shell or batch script. This script should do the following tasks:

call RMAN an execute an RMAN script

backup database
backup archivelogs
delete archivelogs

delete old backups (with RMAN commands)
send the logfile to the admin

Some people additionally run an export with datapump after the daily RMAN backup. This can be useful sometimes. But I never use this option. And it should never replace an RMAN backup!
Comment: I'd disagree that alternatives are not as reliable as rman. Maybe they don't have as many features as rman, but reliable? sure.
Comment: What alternatives are you talking about? exp or expdp is not an option. Backups with `begin backup` and `end backup` can cause problems on huge databases. 3ed party tools like netbackup use RMAN to backup the database.
Comment: @ora-600: setting datafiles in  backup mode is a reliable method for doing backups. It was the method that was used before RMAN was released and it is used today by tools that uses snapshots of file systems  for the backup like Netapps SnapManager for Oracle.
Comment: Back then when setting tablespaces into backup mode was the default method we did not have tablespaces with TB size. Snapshots are nice but what do you do when you get block corruption? I'm still pretty sure that I would not want to rely on a backup other than an rman backup.
Comment: In the last months I experienced the problems which snapshots can cause. A customer uses snapshots additionally to RMAN. When the snapshot is created the database enters backup mode for a very short period of time. Somehow it happened several times that the snapshot mechanism failed to release the backup mode which caused to database to crash after some hours (for obvious reasons). In other databases this will not take hours on some it might take days.
Answer: At the risk of annoying the RMAN fanatics and also actually answering this question by giving possible viable alternatives, it can be done.

you can use datapump (or for that matter imp/exp) to create consistent full logical backups scheduled via cron (or however Windows does scheduling).
you can also take cold physical backups by shutting the database down and using O/S commands in a batch file to copy away the variety of data and config files before restarting the database.

These methods worked fine before RMAN existed and will work fine now, but they do have a number of drawbacks that can impact business continuity rather heavily, but if you have a small database and it doesn't need to be available all the time or you can take a long time to recover if something goes wrong and you don't mind losing changes since the last backup point, then these can still be good working choices.  As a bonus these options don't need archivelog mode either so you can save yourself the performance overhead.

you could do cold backups and archivelogging, scripting logs to tape periodically yourself but you'd have to follow a more complex manual recovery process to roll-forward.
you could also use the export option in SQL Developer to save your database schema objects as DDL and INSERT statements.  This would only be consistent if you closed your application first but might be a viable alternative in some cases (small read-only datasets for example).  Good for migrating data to other database platforms too; one thing that RMAN sucks at.
you can improve on the cold backup by using a split mirror solution of some kind (this was a really massive thing on HPUX for a while) to reduce the downtime to a minute or less.  Cheap RAID 5 arrays all but killed this off but if you have RAID mirroring you can split it and take the backups from the mirror and then resync the mirror you could party like it was 1999.
you can also do all these things via a data guard instance without interrupting or loading your main production database.

Note:
RMAN is very handy at backing up Oracle stuff so you really should use it as a first choice solution.  It's not at all hard to use and much less expensive and complex than trying never to use it, especially as your database grows and the expectation for downtime shrinks.
RMAN is also really good at the recovery bit; much better than most DBAs are at scripting stuff themselves IME - and this is what really makes it worth while as a backup tool.  I know that you didn't ask about recovery but I'll take it that you actually want backups that you can use to get back to a working database (update your question if recovery isn't an important factor because then we can talk about the no-backup solution).  Backups are boring but recovery isn't. Performing a full point-in-time recovery after an actual failure is fantastic - it makes you feel like a god (almost for a minute anyways) even if you only used two statements to do it.  Finding out that recovery isn't possible after working most of the night because the former DBA's script missed the first log file created after the full backup from the tape gives you a homicidal headache.  RMAN is your friend.
Comment: Cold backups hurt the performance of Oracle a lot. I would try to avoid it when ever possible.


Need help making the nodules on buddhas head

Question: hey guys im working on a buddha statue for our server in conan exiles and i need help understanding how to make the details on buddhas head. I want to sculpt one of the spherical nodules you see on his head and then essentially be able to copy and paste them so im not sitting here doing one by one when he has 100+ of them on his head. Just as a forewarning i am using dynamic topology for sculpting with mirroring on incase that changes anything.
Comment: You don't need to sculpt them IMO. Model just one and array it along the curves.
Comment: im 100% new to blender so im not quite entirely sure what you mean by this? should i open a new file and try to make a sphere and what do you mean by array it along the curves?
Comment: nvm i figured it out =D making spheres and torus's to make the single model then ive been using shift + d to duplicate it and place them and then mirroring it on the other side. thanks guys
Answer: Model the detail and array it along the curve. Place many curves with the arrayed meshes around the head.

Add a curve and wrap it around the head. Select your mesh (detail), add an array modifier to it and increase its count. Adjust its offset also. Make sure that the curve and mesh have the origins point set in the same position. Next add a curve modifier to your mesh. Now when you translate the curve's segments the mesh follows it.
Comment: You can add a shrinkwrap modifier to the curve so that if follows the curvature of the head.
Answer: answered above
I figured it out, making spheres and torus's to make the single model then I've been using Shift+D to duplicate it and place them and then mirroring it on the other side.
So from sculpting mode I went back into object mode, once in object mode I made a sphere under the create tab.
I scaled the object down using the tools, next I created a torus under the create menu.
I scaled the torus down and placed it into the sphere, then hit Shift+D to duplicate the torus and moved it outwards along the z axis.
Then used the scale tool to shrink the second one down, and continued this til I got 4 rings.
Upon the last ring i selected the sphere to drag it out more and sized it down so the center would protrude more.
Once the bead or nodule was to my liking i selected the base ring along with the other rings and then selected the sphere last (to make sure it'd be the parent), press Ctrp+P and selected object, to parent them all together.
After parenting them I could Shift+D and duplicate the entire bead/nodule.


Log4net with SyslogAppender, 1kb message limit

Question: Has anyone found a way to get around this? Or a better technique to conglomerate logging from multiple web servers reliably?
Any ideas on good log4net log file analysis tools too (plain text not XML) - apart from good 'ol grep of course :)
Answer: I read about logFaces on another question, or you could use a socket appender and write your own server. logFaces describes itself as a "Log server, aggregator & viewer" but I'm yet to try it.
Answer: The database-based appenders are great for collecting logs from multiple servers.
Answer: The 1024 byte limit is part of the syslog RFC (section 4.1), as is UDP transport which doesn't have guaranteed delivery (in case you worry about log lines lost in the ether).  I think syslog-ng can solve both these issues, but I'm not a syslog expert.
Answer: The limitation is imposed by the syslog itself, not the appender.
I do not know about log4net, but NLog works perfectly ok with "shared" file target - i.e. multiple processes can write in one and the same file.


Boot from cd drive in GRUB2

Question: How can I add a GRUB2 menu entry to boot from my cd drive? Would I have to chainload it, or is there another way of doing it?
Answer: GRUB2 itself doesn't have support to boot from CD, but it supports booting from ISO files.  You could copy the ISO of the CD you want to boot from, to the hard drive and then create a custom grub entry.
Now with Grub, they say its might be possible.  This method is applicable for all legacy PCs which can't boot from CDROM drive.  It requires the use of memdisk.bin, and sbootmgr.dsk.  For instructions, see Boot CDROM through GRUB.
The links to download sbootmgr, and memdisk no longer works.  But you can download them by clicking on their respective links.
sbootmgr.dsk, and memdisk.bin
Comment: Not at all what I wanted to hear, but one shouldn't shoot the messenger :-) The whole point of booting from the DVD is to keep it free of entanglements with existing OSs on the machine.  I suppose I _could_ create an entirely separate partition for my ISO...

Boot from cd drive in GRUB2


Do inline embeds detract from readability and useability of a news article?

Question: If you have a news article, with a related gallery embedded after paragraph three, a twitter embed after a relevant paragraph referencing the Tweet, and a "for more information on x" reference link, how is the readability and useability of the text affected?
The main goal is to get people to read as much of the story as possible, on desktop and on mobile.
My gut feeling is that relevancy plays a large part, but I also feel that breaking a giant wall of text into easily digestible chunks can actually INCREASE the interaction with the story.
Answer: Providing a related piece of information associated with a paragraph below it in a news article would always provide a better user experience as a reader would otherwise have to scroll or navigate to a different place and try to find a matching info associated to the paragraph he might have just finished reading. The latter would anyway INCREASE the interaction with the story but, at the cost of providing a good user experience.
Breaking down a large article into smaller chunks would always help in achieving better readability. Smaller paragraphs with proper associated infomation can make the user feel easy going while reading compared to that of a large body of text even if it's in paragraphs.


is it worth switching from Joomla to Drupal for better CiviCRM integration?

Question: Our site is currently using Joomla 2.5.27 and Civi 4.4.11. We need to either upgrade Joomla & CiviCRM to the latest or migrate our site to a drupal platform. Both sound like a lot of work. But we have some  kinks in optimally using Civi that appear to be the result of incompatibility w/ Joomla. I am not a developer but am a knowledgeable user; I have some tech volunteers who are prepared to help me once I make a decision. Any thoughts?
Answer: Developers tend to prefer Drupal over Joomla. But each CMS has it's pros & cons. You need to figure out which one is better for you.
For example if you have a Joomla extension that gives you functionality which would require a lot of custom coding in Drupal, it would make sense to stay with Joomla.
The kinks you mention may not be around in that later versions of Joomla & CiviCRM, but there may be others, so you really need to do some testing to make a decision that's right for you.
Demos are available at: https://civicrm.org/demo - but they are reset periodically so you may prefer to create a sandbox on your own server or local machine for testing.
Answer: The big advantages that we typically use with Drupal are
Views: the ability to build query/displays that can be used in many different settings
Webforms: ability to push/pull data from civi in a form building tool that has a lot of extras
CiviCRM Entity: means Drupal can see/use CiviCRM data as if it is a Drupal Entity.
Whether it is 'worth' the effort is harder to judge as that would depend on what you have in the CMS and how easy it would be to rebuild that in Drupal. The Joomla to Drupal migration/conversion process has worked well for us in the past.
If we had a client on old Joomla, and if upgrading Joomla would involve rebuilding theme, rethinking content types, etc, then we 'would' migrate to Drupal. But that is opinion/preference, not a 'solution'.


If I have clamav do I need to install rootkit hunter

Question: So I have clamav the antivirus but is that a protection against rootkits or do I need to install rootkit hunter as well with clamav?
Comment: @Zacharee1 That's a discussable opinion. The level of security you need always depends on your actions and you level of paranoia and although there might be less viruses against Ubuntu systems than against Windows systems, it's still recommendable to have antivirus software. At least e.g. if you're downloading stuff you later transfer on Windows machines, it's great to be able to scan it first. Also, malicious email attachments can reach your inbox without any shady actions from your side. You see, I strongly disagree with your advice.
Comment: @Zacharee1 Google uses Ubuntu (server) also scans the data it receives and share ( the downloads you do) with anti-virus
Comment: However, my level of paranoia hasn't made me worry about rootkits yet, so i can't give a definitive answer for that. But I'll call the paranoia expert in to share is panda-fu with you! ;D
Comment: @ByteCommander works for me :)
Answer: Clamav only acts as an anti-virus, and does not protect you against rootkits. In the opinion of most people viruses are not such a big threat on Linux, however we can all agree that rootkits are so it is good to protect yourself against them.
Though rkhunter will need to be installed on a fresh install before any software or updates are installed because it looks at changes in the system, and assumes the system it is installed on is safe, and then compares that to the system's state later on when you do a scan.
So if you have a rootkit already, and you install rkhunter, it won't be able to tell if you have one or not.
Another option is OSSEC HIDS (Host Intrusion Detection System - which is not required to be installed on a fresh install, and will be able to detect a rootkit on a system even if it is installed after the rootkit (in most cases)) which can detect rootkits as well as a larger range of system activities.
Comment: @HenryWHHack: Yes, rootkits are a major threat in and outside the Linux world so it is very important to protect against them, because they actually make your system hide them (and potentially other malware) so without a program such as `rkhunter` you won't know that they are there, and they can even be used to hide malware which ClamAV would otherwise detect. They can even completely disable all of your protection while making your computer say that all is well.
Comment: So rkhunter is important for security?


Can I run CAT6 FTP cables parallel to electrical cable in the same conduit?

Question: Can I run CAT6 FTP cables beside to electrical cable (220v 1 amp) in same PVC Trunking ?
Comment: Where are you on this planet? Is running a second conduit an option? Is this an indoor or an outdoor run for that matter?
Comment: What is the voltage rating and are there separate box areas at each end to separate the voltage connections from the data. Other than that we would need to know where in the world you are as 3phase asked, different rules for different areas.
Comment: *"I plan to kill myself or set my house on fire. Is this a good way of going about it?"*
Answer: Absolutely not.
Low voltage (LV) and mains cannot share a conduit.
Further, you cannot attach anything else to the outside of the electrical conduit.  So forget about ty-wrapping the LV cable to the  outside of the conduit...
Comment: Define: "conduit". If the OP is from Western European countries where wall-mounted trunking is commonplace (and it is permissable within the local building regs to carry mains AC, ethernet, phone lines, TV jacks, etc all simultaneously) then I can see why people refer to it as a conduit - whereas in the US conduit tends to refer to much narrower flexible tubing not intended for carrying more than a couple of cables - and both are made of PVC. This is an example of a multi-media + mains trunking: https://www.lindrickelectrical.co.uk/lighting-gallery/commercial-12/
Comment: @Dai -- "conduit" in the US is a tubular raceway, made from metal or plastic (the latter is often PVC, but glass-epoxy can also be used), either rigid or flexible, that can be used to carry conductors or communications cables, and can be installed either exposed or concealed.  The closest US equivalent to European-style "trunking" is a product called *surface raceway* that provides a rectangular or molding-shaped channel along the surface of the wall that can carry mains or LV wiring, or both if the system has dividers in it to provide separate mains and LV compartments
Answer: You can run cables parallel outside conduit. Ideally a few inches apart but in practice right next to each other is usually OK.
But you can't run them together inside conduit. Plus, inside conduit you would be better off for the electrical cable using individual wires (appropriately sized & rated) instead, which is not an option for the CAT6 anyway.
Answer: Not in the same conduit as 120 or 220 - 240VAC, no.
Parallel to is no big deal, people who fuss over things that will generally have no effect do like to keep a foot/30cm between them, ideally, but in point of fact the signal design is such that interference between 50/60 Hz powerlines and 100+MHz network wiring is not really a problem.
Comment: From my own experience doing office installations it can make a difference. I've had lines fail to real 1Gbps due to interference when tested, and moving the line over slightly fixing the problem. Incredibly rare, and entirely possible things other than the mains was the cause of interference mind.
Comment: Mains power is 50/60Hz, but that doesn't stop any device to either intentionally (powerLAN adapters) or unintentionally inject higher frequency noise into the power network.
Comment: ...which the differential signal twisted pairs largely reject, by design. *Incredibly rare* matches my own extensive experience of many cable segments attached to smart switches that report error rates.
Comment: I've seen trouble.  There was an IIRC 440V 400A power bus up near the ceiling.  Some electricians hooked up network wires--doing things like throwing a wire over that power bus to keep it out of the way.  Despite everything they did it worked, but with a high error rate.  Note that this was 10/100 base-T, not modern stuff.
Comment: Years ago, when the company I ran IT for built a building with an office in the front, I specified the power and data conduits buried in the concrete slab to be a foot apart.  I know it probably would have been OK a bit closer, but there was just no reason in my mind to push it, given that future improvements in network speeds might make newer technology more sensitive to crosstalk than the then-current tech.
Comment: When they're too close, one can also use shielded/braided electrical cable. And concerning network cables, SFTP is better shielded than FTP. If one of both is completely un-shielded, you've got an antenna... keeping an eye on packet loss is suggested, because it's an indicator for interference. There's also specialized probes for EMI.
Answer: An important question for you to ask is this: what is the difference between Cat5e and Cat6?
The answer is shielding. Cat6 adds a layer of shielding over Cat5e. That shielding is designed to reduce electromagnetic(EMF) interference so you can get more signal through it. Cat 7 and 8 add even more shielding.
Electrical wire is a significant source of EMF interference. The more your wires run unshielded and parallel, the more interference they will get. Mere perpendicular crossings are generally limited in how much interference they produce (although you should still limit exposure). As such (ignoring the electrical code), you will render your Cat6 unusable, especially if you want to run 10gB Ethernet.
Answer: I cannot speak to building codes (though I was always told that running low-voltage wiring near high-voltage wiring was a really bad idea, in case of a fire or other damage-- in particular, never do this on either the interior or exterior of a building where they could be struck by an errant forklift or car, and short through each other), but I CAN talk about the signal issues.
Ethernet cables contain eight conductors, formed as four twisted pairs.  The idea of twisted pairs is that they are used as a balanced line, where one line in the pair carries a positive signal, and the other line in the pair carries the inverse of that signal.
Ethernet jacks, meanwhile, are implemented using magnetic isolators-- usually just called "magnetics".  These are tiny air-core transformers, built right into the jacks.
The idea is that the positive and negative signal, applied to the coil forming one side of the transformer in the jack, produce a voltage in the coil in the opposite side of the jack.
Meanwhile, any external noise will introduce a voltage of equal sign and roughly equal magnitude in both lines, such that the net voltage across the lines in the coil due to the noise is very close to zero, and therefore the voltage induced in the opposite side of the magnetic isolator is also very close to zero.
Notice the word "roughly".
When an unshielded Ethernet cable is VERY close to a noisy line-- either an electrical line, or another unshielded signal cable with similar twist rates but higher power-- then the difference in the noise power induced in the two wires in the twisted pair can be significant enough to induce a significant voltage across the magnetic.
Ethernet energy levels are fairly low partly to ensure that adjacent Ethernet cables in a trunk can coexist without much crosstalk.  But with power lines, antenna feeds, and so forth, this can be an issue.
Answer: The answer is: NO! Due to the emg interference.
Comment: Hello, and welcome to Home Improvement. I think you mean "EMI", but that's actually a minor concern; Cat6 cables are extremely well-protected against interference. And, you should probably [take our tour](//diy.stackexchange.com/tour) so you'll know how best to contribute here.
Answer: NEC 2020, and I don't think it's changed for the last 20 years

https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=70
Article 300 - General Requirements for Wiring Methods & Materials
  300.3(C)(1) Conductors of different systems 1000 volts or less
Conductors of ac & dc circuits rated to 1000 volts nominal or less, shall be permitted to occupy the same equipment wiring enclosure, cable, or raceway.  All conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the enclosure, cable, or raceway.

So first off there is no NEC code prohibiting you from doing so.  If there is then someone should specifically reference it.  No one has in any of the responses here.  Any many of the responses are downright poor.
of logical importance: occupy the same enclosure, cable, or raceway;  If you believe some nec code prohibits from doing what was asked then that would also have to mean when current carrying conductors didn't ALL operate at the same [nominal] voltage then we would have separate conduits for 120v vs 208v vs 240v vs 480v.  That is not the case.  Per 300.3c1 everything being less than 1000 volts it's simply the minimum wire insulation rating has to be observed.
Cat5e and cat6 and any other Ethernet cable is all rated to 300v.  I believe RG-6 coax is as well.  If you find a specific brand with inking saying to 600v then great even better but i don't think they exist.
https://www.mysouthwire.com/medias/sys_master/product-specifications/product-specifications/hd8/h0c/8858069565470.pdf
All romex (nm-b) and any pull wire like thhn is all rated to 600v.  For any U.S. household which is usually 240 volt and below you basically have nothing to worry about with regards voltage and hazards.  Only if your 600v rated romex was being used for 480v then you would not be able to run a cat6 cable in same enclosure, because the cat6 cable insulation is only rated to 300v.
as for signaling and quality of over the CAT 5e/6/7 or RG-6 cable, there is no hazard once the insulation requirements are met.  At most if it is signaling for something important, to some legally required system or emergency system as called out in NEC section 7 then it would be reasonable to not run your cat 5/6/7 or rg-6 in same conduit because the system that goes to is that important.  but the NEC is not concerned about your xfinity and internet signal quality.
the running of cat5/6/7 or rg6 next to romex and/or wire in conduit is blown way out of proportion.  If it were anywhere close to true then every commercial network closet with a rats nest of cat5e UTP all run intertwined and velco strapped with 120v and 240 power cables to equipment would not work.  They work just fine.
it is the twists per inch that differentiates cat 5 vs cat6 vs cat7 and not necessarily cable shielding.  There is UTP (unshielded twisted pair) and STP (shielded twisted pair) which is independent of CAT-#.
the best way to go in any event is with STP (or FTP) or quad-shield coax.  But with FTP or STP you have to use the corresponding metal rj45 connectors to maintain the shielding.  Or you can just buy a 100' STP pre-made cat6 cable.  Likewise with coax simply use RG6 quad shield.  Either of which, having a 300v insulation rating, is thus permitted to be run alongside your 120v or 240v wires in your conduit.  You would then really only need to worry about conduit fill.  for cat6 @ 1gbps I think u would be fine but if you're wanting to do a long run at 10Gbe speeds then I would definitely do FTP or STP.
Comment: Your Code cite is inapplicable to communications cable.  800.133(A)(1)(c) governs the OP's situation, and *prohibits* the mixing of mains wiring with communications cabling unless a listed divider or permanent barrier is present in the enclosing raceway to separate the mains and comms wiring.


Order by varchar mysql

Question: Is there anyother alternative for order by varchar clause? At worst case consider I want to order by varchar column that is not indexed. When I tested a query with loads of data it took many times to execute. It is obvious that it will take much time. But is there any other alternative approach for this without indexing that column?
Comment: Maybe there's a way to solve the underlying problem another way. Why can't you index the column? Or why don't you want to index it? What permissions do you have on this database and table?
Answer: Nope. If you order by a not indexed column then the server HAS to load all the results into memory and can only then start sorting them. That is heavy - not sure how mySql does it, but on SqlServer that will also tax the tempdb for the temporary holding of the data. If it is a lot of data that may be super slow due to memory flowing over onto the hard disc.
Physics and logic can not be cheated, sadly.

Order by varchar mysql


Reply traffic lost when using an NVA to SNAT

Question: I am trying to implement the following in a lab subscription, as described in https://learn.microsoft.com/en-us/azure/architecture/guide/networking/ipv4-exhaustion#implement-snat-via-third-party-nvas (Method 1: Nonroutable landing zone spoke virtual networks / Outbound dependencies / Implement SNAT via third-party NVAs):

At this stage, it is purely a learning exercise for me, but the eventual goal is to support interconnection with a series of existing on-premises estates, where VPNs to each will be established either to a VPN Gateway or (more likely) to a third-party NVA in the VNET designated Routable Hub.
In the eventual setup there will be many Landing zones and, for autonomy (read: political) reasons, I will not have oversight of the IP address spaces used by each of the LZ spokes, so am looking to corral the outbound traffic from those spokes into an address space I can manage, using a per-zone Routable LZ hub VNET (which I can control) as an intermediary.
In the lab, I have successfully established:

VPN between On-premises and Routable hub (A), using a third-party NVA
VNET peering between Routable hub (A) and Routable LZ hub (B)

a routing table exists in (B) to route the on-premises subnet via the NVA
a VM in (B) can ping the NVA in (A)
a VM in (B) can ping an on-premises device, routing via the NVA

VNET peering between Routable LZ hub (B) and LZ spoke (C)

a VM in (B) can ping a VM in (C), via the default route
a VM in (C) can ping a VM in (B), via the default route

I am now trying to apply the principles described in Outbound dependencies, where a VM in (C) might need access to an on-premises device.  As such, I have added:

an NVA device to (B), specifically a one-armed pfSense VM from the Azure Marketplace
a routing table to (C), which routes the on-premises subnet via the pfSense
I have configured an Outbound NAT rule on the pfSense to translate anything from (C)'s address space to the pfSense's address in (B)'s address space.

With this in place, I can see:

traffic from the VM in (C) arrive at the pfSense
the pfSense apply SNAT to its address, and dispatch to (B)'s default gateway
the NVA in (A) accepts the traffic from (B) with the source address of the pfSense
the NVA send across the VPN, targeting the on-premises device
the target on-premises device sees the traffic, accepts it and replies
the NVA in (A) receives the reply traffic and forwards to the pfSense in (B), which the pfSense accepts
the pfSense in (B) reverses the SNAT and forwards to the address of the VM in (C)

But the reply traffic never appears on the VM in (C).
Below is some of the "evidence" of what I have said I can see:

The VM IP is 10.0.16.254; it exists in (C), subnet 10.0.16.0/20
The pfSense IP is 172.23.2.6; it exists in (B), subnet 172.23.2.0/24
The target on-premises device IP is 172.18.4.80; subnet 172.18.0.0/16 (via VPN)

If I am reading it correctly, the pfSense correctly SNATs and un-SNATs the traffic, but the traffic is dropped somewhere during the reply, between the pfSense in (B) and the VM in (C).
There are NSGs on the interfaces of the pfSense and the VM, but I believe these are correct -- insofar as they both have a rule which allows traffic from 172.18.0.0/16 to VirtualNetwork at some point before the three default rules.
(I recognise that, within NSGs, VirtualNetwork does not encompass include the on-premises subnet, as it is not associated directly with any VNET, but I believe should include all peered VNET subnets.)
Other things that may be of note (but may be red-herrings):

The VM in (C) is configured to log all accepted and blocked packets
A tcpping from the pfSense in (B) to a valid service on the VM in (C) seem to reach the VM and be logged
A tcpping from pfSense to an invalid service on the VM seem not to be logged (but it may be a delay in log flush)

I'm sure I've missed something simple but what else might be preventing the reply traffic reaching the VM in (C), after it has been un-SNAT'd by the pfSense in (B)...?
PS. Note that, since this is as much a learning exercise for me as anything else, I am particularly interested in the model as diagrammed by Microsoft at this point, rather than any alternatives -- including alt diagrams on that same page
PPS. Also note that, while the target diagram indicates two SNAT NVAs with a Front-end Load Balancer IP, I currently only have one SNAT NVA and no LB IP -- I am just trying to get the principles working initially and will look at high-availablity later.  If the LB IP is providing the missing piece of the puzzle, then please advise.
Answer: It appears that, in order for the un-SNAT'd packets to leave the pfSense, the NIC assigned to the pfSense VM must be configured with the Enable IP forwarding option.
Enabling this option disables an internal Azure restriction which prevents a VM sending network traffic using a different source IP address than the private address which has been assigned to it.  This is essential if the VM is acting as a NAT device.
This seems to be an error in the pfSense firewall we installed from the Azure Marketplace, in that it does not automatically enable this setting on the NIC that it creates.
After enabling this option, all traffic flowed as described in the diagram.


How can I know if something is a Lorentz transformation?

Question: I'm studying special relativity and was wondering, if someone were to give me a matrix, is there a way or a procedure to check if that matrix corresponds to a Lorentz transformation? Even if the matrix contains projectors or other weird things?
Comment: What is your definition of "Lorentz transformation" and what specific problem do you have in telling whether any given matrix fulfills it?
Answer: Yes, it needs to leave the Minkowski metric invariant:
$$ \Lambda^T\eta\Lambda=\eta. $$
Answer: The set of Lorentz transformations is defined as the set of all operators $\Lambda$ (or equivalently, matrices) that satisfy
$$ \eta(u,v) = \eta(\Lambda\,u,\Lambda\,v)\:\:\:\forall u,v\:\: \text{vectors in Minkowski spacetime},$$
where $\eta$ is the Minkowski metric.
In matrix representation this translates to the following statement:
$$u^T \eta v = (\Lambda\,u)^T\eta(\Lambda\,v)\:\:\:\forall u,v\:\: \text{vectors in Minkowski spacetime},$$
$$\:\:\:\:\:\:= u^T\Lambda^T\eta\Lambda\,v\:\:\:\forall u,v\:\: \text{vectors in Minkowski spacetime}.$$
Given that this statement must be valid for all $u$ and $v$, we obtain the condition:
$$\eta = \Lambda^T\eta \Lambda,$$
where in the equation above $\eta$ is the matrix associated with the Minkowski metric. In an orthonormal frame, it reads $\eta = \text{diag}(-1,1,1,1)$.
However, one is usually only interested in the proper orthochronus Lorentz Transformations, associated with Lorentz transformations that preserve the future time direction and do not invert the spatial directions. If you are looking for this set of Lorentz Transformations, you should also check that the matrix is invariant with respect the matrices associated with space and time inversion.
Answer: Write the unit time vector and three unit space vectors.  Send each to your given operator and note what comes out.  All four results should remain unit space-time length, and all possible pairs should be orthogonal.
Of course, unit vectors have a very simple form. All you're doing is reading out columns of the matrix. No hard math, just looking. Just remember that lengths and dot products must use the mixed-sign spacetime metric, -+++ (or +---).


Now can I group custom post types together?

Question: Now that wordpress 3.1 is out, where is the documentation for grouping custom post types together in the wp backend?
Comment: When you say group, what do you actually mean sorry? I'm not following. Do you mean relate post types to one another?
Comment: But this method disappears submenu of custom post. Links for editing custom taxonomies are not present. How to do it and not lose this submenu?
Answer: If you are wondering how to group multiple post types under one menu, you can easily do this with the show_in_menu argument when setting up your menu. See below:
$args = array(
 'public' => true,
 'show_ui' => true,
 'query_var' => true,
 'rewrite' => true,
 'capability_type' => 'post',
 'hierarchical' => false,
 'show_in_menu' => 'your-custom-menu-slug.php',
 'menu_position' => null,
 'supports' => array('title','editor','custom-fields'),
 'has_archive' => true
);
register_post_type('your-post-type',$args);

Note: For this to work, show_ui must also be set to true.
Then you would create a menu using the add_menu_page function.
function add_your_menu() {
  add_menu_page( 'Multiple Post Types Page', 'Multiple Post Types', 'manage_options', 'your-custom-menu-slug.php', 'your_menu_function');
  // add_submenu_page() if you want subpages, but not necessary
}
add_action('admin_menu', 'add_your_menu');

In the same fashion, you can also attach post types to any existing menu. For example, it might be useful to attach certain post types to 'Posts' and others to 'Pages', while others might belong in 'Tools'. If you attach to an existing menu, you can ignore the add_menu_page function above and just modify the $args when registering your custom post type.
Comment: Thank for this answer. It work, but it only display all post of each custom post type and not display taxonomy(or category) of that of each custom post type. Can you help me, please? Thank you very much.
Comment: Still one of the best and simplest answers. Works as expected.
Comment: Is there a way to show the CPT submenu options with this solution?
Answer: Just for future reference as this page ranks quite high in Google, you are not required to create a custom menu item if you just want to group some common post types together in the same menu, you can group together by using existing menu items:
By defining a 'master' post type, you can do something similar too:
'show_in_menu' => 'edit.php?post_type=a_master_post_type',

Comment: For that, you would need a hierarchy, while the accepted answer is more general.


How can I use screen for training and/or remote assistance?

Question: So, in theory I can log in as an admin user and have someone else log in as the same user or a different user over an SSH session and have both users attached to the same screen. In our case we have a rather complex environment setup and sometimes need remote assistance with it. How is this done? Do we both need to be the same user?
Answer: I understand you are aimed at an application for training, and although your question specifically states screen, let me suggest tmux.
With tmux you can create sessions, to which you can connect from several computers. I have only done it for the same user, so I do not know if it is possible to attach to sessions created by a different user.
You can have even several sessions on the same machine. For example, you may run the following command to create a new session. Run it with the same user your pupil is going to use. You can name the session whatever you want (I chose lesson01).
$ tmux new-session -s lesson01

Then, your padawan logs onto your machine over SSH using the same user as before. He may then run this command to attach to your session.
$ tmux attach-session -t lesson01

Whatever you time in one terminal, should automatically appear on the other. Also, with tmux you split the terminal in two (leaving one for you, and the other for your pupil).
I hope you find this useful for education and training purposes. Again, sorry not to answer how it is done with screen.
Comment: @RuiFRibeiro I searched stackexchange and found this. I hope you find it useful. http://unix.stackexchange.com/questions/2523/what-are-other-ways-to-share-a-tmux-session-between-two-users
Comment: The idea if fine, for training or education purposes I would rather much prefer that the trainee is with a less privilege user.
Answer: An alternative approach to redirect the output of your terminal to a terminal of some other user is:
Doing at your terminal:
mkfifo foo; script -f foo

Use the who command to see the terminal of the other user; and on another terminal of yours, redirect the output to the terminal of the other user, as root:
cat foo >> /dev/pts/2


doubt regarding cash flow statement of bajaj finance?

Question: I need a little here understanding this cash flow for Bajaj Finance. The cash flow here from operating activties is in negative and goes on increasing in negative value. While that for financing activities is positive and goes on to increase. However this stock is considered to be performing really well. And I see a similar trend in a couple of other finance businesses as well. Can someone help me understand this?cash flow of bajaj finance
Answer: Generally the Cash from operating activities is revenue generated by company for sale of goods less of expenses. This is a good indication if the company can survive long term, generally positive for manufacturing company.
  https://www.investopedia.com/terms/o/operating-activities.asp
The cash from financial activities show how the company is managing its capital and borrowing and the interest it is paying for funds. Generally negative for a manufacturing company
https://www.investopedia.com/terms/c/cashflowfromfinancing.asp
However in case of finance companies, they don't sell anything; so all the costs salary, building, marketing, etc becomes operating loss. The money by a financial company is always by lending and hence positive.
As the financial statements are pretty standard way of representing things, it gives a different view.


MailChimp API 3.0 xhr subscribe 501 error

Question: I am trying to subscribe users to my mailchimp list using this snippet:
function subscribeUser(name, email) {
  var xhr = new XMLHttpRequest();
  var endpoint = 'https://<dc>.api.mailchimp.com/3.0/lists/<list>/members/';
  var data = {};
  data.email_address = email;
  data.status = "subscribed";
  data.merge_fields = {};
  data.merge_fields.NAME = name;
  xhr.open("POST", endpoint, true);
  xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
  xhr.setRequestHeader("Authorization", "apikey <key>");
  xhr.onreadystatechange = function() {
    if(xhr.readyState == 4 && xhr.status == 200) {
      alert(xhr.responseText);
    }
  }
  xhr.send(data);
}

It generates this error in chrome:
I am unable to write ajax based services to update lists. Because you guys did not add the Access Control header. I cannot send a simple xhr to your endpoint using a modern browser.
XMLHttpRequest cannot load https://<dc>.api.mailchimp.com/3.0/lists/<list>/members/. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8000' is therefore not allowed access. The response had HTTP status code 501.

Mine is a static website and I would like to keep it that way. No backend is needed, hosted on github. So I need a JS solution to this.
Answer: They currently do not allow client-side access to their API. Their response to a similar question in comments:

We do not support accessing the API via client-side Javascript to
  avoid the security issue of passing your API Key along to your users.


Use bidirectional SSL with CAC from phone

Question: Is it possible to extract the certificate from a CAC (DOD common access card) and install it on a phone so that access to websites using bidirectional SSL can be done from a user phone.  Ideally, the certificate would still be protected by a PIN/passphrase.  Initially interested in Android phones.
Answer: The CAC seems to be a typical smartcard where the private key is stored on the card itself and crypto operations involving the private key like signing are also done on the card. Such smartcards do not allow extraction of the private key. In fact, that is the main purpose of these cards that any use of the private key should explicitly require physical possession of the smartcard.
In other words: you will not be able to extract the necessary secrets (private key of the certificate) from the card so that you can use these to authenticate yourself without the physical card being involved.
Answer: As @Steffen says, unless there's some horrible vulnerability with the CAC card, you shouldn't be able to extract the private key from an existing card. That's kind of the whole point of those things.
That said, at card creation time, you could load the same private key into a physical CAC card and into the Android device (assuming that your department policy will allow it), or simply have two CAC cards registered to you, one physical and one in an app.
As an example, the Entrust Mobile Smart Credential mobile app emulates being a smart card either to a laptop over USB / bluetooth, or to a door reader over NFC. If your IT department supports a solution like that, maybe something like that might address your needs?
Disclaimer: I work for Entrust and I do not have any experience with another app that might do the same thing.


Can I have a sub panel right below the attic access?

Question: I'm rewiring an old house where I've already installed a 50 amp sub-panel. Now the carpenter decided to put his attic access in the ceiling right above the panel is this permissible.
Comment: are you located in the USA? Permissible depends on the code being followed.
Answer: As Steven said, it depends on the applicable code. I doubt any code is going to be that specific. So it will be up to the local authority having jurisdiction to interpret what the code does say and decide if it applies to your situation. As such, no one here can accurately answer this unless they happen to represent your LAHJ.
For example, the NEC simply says that over-current devices be readily accessible. Readily accessible in part is defined as devices need to be able to be quickly operated without the need to remove any obstacles. So the attic access alone would seem to comply as it does not affect access to the breakers.
However, to effectively use an attic access, one must place a ladder, which could block access to the breakers, requiring removal before operation is possible. This would cause the panel location to not comply.
In cases of contradicting interpretations, the LAHJ must decide what interpretation best represents the code's intent. Since access to breakers could be most important when someone is working in the attic with a ladder in place, I personally would rule that this arrangement is not in compliance. But I am not your LAHJ.
The short answer is you have to ask your electrical inspector.
Answer: i think your biggest concern is that NO WIRES be run on tops of joists within Six feet of an attic access. good luck with THAT one!


how to import linux command in shell script file as  the value of a variable ?

Question: I am using Fedora 10. If I write java -version in terminal, it gives me java version. I want to write a shell script file to check whether the java version is greater than 1.5.
The main problem is that I donot know how to assign the value of java -version command as to a variable of shell script.
How to create shell script file for that ?
Answer: As answered above, you can use backticks or (if your keyboard doesn't have them) use the following format:
JAVA_VERSION=$(command)
Answer: Use backticks:
JAVA_VERSION=`java-version`

Comment: can i confirm you did get a result in JAVA_VERSION variable?
Answer: you should direct stderr to stdout
$ var=$(java -version 2>&1)
$ set -- $var
$ echo $3
"1.6.0_0"
$ echo ${3//[._\"]/}
1600

Now you can compare $ver to see if its greater than 1500.
Answer: All the above Answer will work for you. below are the common example which you can use to get the value of variable:
JAVA_VERSION=`java-version` or JAVA_VERSION="java-version" or JAVA_VERSION=$(command)

The way is to set the value of variable is many. You can use your easiest way to fulfill your requirement. Like I'm using
var=$(awk -F'"' '/^variable=/ {print $2}' script1.sh )
echo $var


Does Braintree work with magento2 for automated recurring billing?

Question: Does Braintree work with magento2 for automated recurring billing? Or is authorize.net our only solution?
Answer: Magento2 does not have any kind of recurring billing solution built-in. Magento1 had recurring profiles, but that functionality was dropped in M2.
At present, there are two third-party extensions (that I'm aware of) offering this kind of functionality for M2:

Magenest's Subscriptions and Recurring Payments
ParadoxLabs' Adaptive Subscriptions

Full disclosure: I wrote the ParadoxLabs module. I can't speak to Magenest's solution in terms of quality or what payment methods it might support. Adaptive Subscriptions is the only one audited and available on the Magento Marketplace.
The ParadoxLabs module only supports Authorize.Net as of this writing (as you may be aware), but we have support for Braintree and PayPal PayFlow Pro well underway, and others planned. Please contact us directly if you'd like to know more or discuss this further.
Thanks!
Comment: Thanks Ryan, One more question as we want to use Paradox and are about to install authorize.net.

We use Netsuite. Do you know if NetSuite supports authorize.net?
Do you know if they expose transaction details in order API?

Thanks.
Comment: I haven't worked with NetSuite before personally, but Magento does expose transaction details via the official API. Depends on what exactly NetSuite requires. I think I saw an email from you about this; we'll respond, if we haven't already.


Marketing Cloud Lightning

Question: How can we enable the Lightning UI within Marketing Cloud? I tried to find any settings in Admin setting but can't find anything.
Answer: Lightning's a CRM/Force.com thing. In Marketing Cloud, it's a buzzword that's loosely used to refer to incremental updates to the UI that pinch some of the styling of "Lightning Design System" - the CSS used by some CRM users.
There's no button to press or checkbox to tick. Bot you'll see certain parts of Marketing Cloud that have been spruced up "Lightning Style".
Comment: Hi Andrew, thanks. In most of the new released demos/feature videos the Marketing Cloud looks 100% Lightning. So we just have to be patient for new releases?
Comment: Andrew is right.. Lightning is mainly a SFDC thing and SFMC uses fuelux. There are plans on the product roadmap to move SFMC to lightning UI (Aura) but no clear timelines

Marketing Cloud Lightning


Font in Terminal looks corrupted

Question: Hello I have the next problem, Im a new Linux user and I don't know what I do so my shell look so different as default one.
and the letter are kind of united, I'ved seen some similar posts but any of them worked.
also: sorry for my broken english.
Answer: This issue may be caused by two things:
1) you have modified your system font settings and have set some proportional font (i.e. OpenSans Regular, in which different letters have different widths) as your system monospace font. Solution: install elementary tweaks, go to System Settings > Tweaks > Fonts and choose any monospace font (i.e. Roboto Mono Regular) to be your system monospace font.
2) you have messed only your Terminal's font setting. To fix it in elementary OS 5, run this command:
sudo gsettings set io.elementary.terminal.settings font 'RobotoMono-Regular 10'

Comment: It just doesn't worked I'ved tried both.
Comment: 1. Did you reboot your PC afterwards? 2. Have you been experiencing this issue all the time since the fresh system installation, or only recently?
Comment: yes, every time and no, recently yesterday and the commands to change font doesn't works it stays equal.
Comment: yes, every time I made a change, and no since yesterday. also I've tried reinstalling elementary tweaks, and the font doesn't seems to change and the size.
Comment: I already fix it making a teawks new instalalion rebooting and using the  fix font elementary code you gave me thanks.

Font in Terminal looks corrupted


Proper Guide for printing Report in Dot Matrix Printers

Question: Is there anyone that could give some proper guideness in Printing Reports (e.g. XtraReports)
in Dot Matrix Printers? Or any information printing in Dot Matrix Printers. Can i just print the report as i could print in InkJet/Laser printers? Should i use Stream to LPT1, export the report as RTF and print as bytes[]? Use Escape Codes? Any info for the above targeting C# .NET? I should handle printing my business object for every property to a specific location? HOW?
Answer: If it were me (and 20 years ago it would have been) I'd concentrate on writing the document in GDI properly as a good, well-structured C# program.  From there Windows can render it onscreen or to just about any printer you've got drivers for.
Let Windows worry about the print drivers for actually rendering the GDI document onto paper and handling system things like what port it's connected to (USB, Parallel, etc..) and all of the nasty protocol details.
Please don't wire things to "LPT1", "COM" ports or any of that crap.  Your admins and future users of your software will hate you for it.
Comment: Any example please on this approach?
Comment: There are dozens of books and online tutorials on how to write a GDI program in C#/VB.  Or, hire a programmer to do it for you.


GFCI outlet when vacuum cleaner is plugged in

Question: when i plugin my vacuum cleaner to my bathroom GFCI outlet without turning on the vacuum the GFCI outlet trips. but it works in any other outlets
Comment: Does it work in other GFCI outlets?  You know what a GFCI does, right?  It's a ground fault detector, it's looking for faulty appliances.
Comment: PLease provide sufficient detail:  "other outlets" on the same GFCI run, or outlets elsewhere on a different GFCI run,  or outlets NOT behind a GFCI?
Answer: There are two possibilities:

False Positive

This is rare, but it can happen. More likely with AFCI (because it has a more complex problem detection mechanism) than with GFCI. Extremely unlikely when the plugged in device is off, which is the specific situation here.

True Positive

This means your vacuum cleaner has a ground fault. That is a potentially serious problem. It could be a design issue, but if it used to work and now it doesn't work then it points to a problem such as worn out insulation that is allowing a small amount of current to leak to ground, which will then trip the GFCI.
The way to tell for sure (well, reasonably sure) is to plug the vacuum cleaner into a different GFCI. GFCI has been required for bathroom receptacles and kitchen countertop receptacles for many years, so if you have a GFCI in the bathroom there is a good chance you have a GFCI in the kitchen. If the problem does not happen on any other GFCI then it may indeed be a bad GFCI. If the problem happens on every GFCI then you have a bad vacuum cleaner.
Comment: Think they were required in bathrooms before being required in kitchens.  Early 90s addition only had GFCI in bathroom and outdoor, none in the the kitchen(done by license electrician).
Comment: @crip659 nope the original requirement for GFCI's was for bathrooms and to prevent electrocution's from a device like a hair dryer in the tub. As the NEC can not mandate a update to bathrooms all hair dryers were required to have HFCI protection.
Comment: Concur with reply,  if it's truly a gfci not an afci protected circuit, you've Likely got a fault in the vacuum!
Answer: With the vacuum turned off there is only 1 possibility.
Yes the vacuum could be totally save but have a lighted switch , to ground 6 ma and the GFCI trips
OR another failure.
The cord set has a indirect fault to ground both are the same to the GFCI more than 6ma flowing in the hot to earth and the reason for a trip where a normal outlet works fine.
In both cases it is the same fault an imbalance on the hot and neutral.
One is a valid Ground fault the other is not as the vacuum is operating (or not in this case switch off).
Comment: finally someone with some sense and logic
Answer: maybe your GFCI is just doing its job.
Test it by pushing the Test button.
Since it triggers the GFCI without turning on the power to vacuum cleaner it could be wear and tear off the vacuum cleaner cable.
Vacuum cleaner cable are exposed to high stress levels, twisting, coiling, pulling, dog ?
Either on the cable plug side or on the vacuum cleaner connection, there might be a very small short inside the cable, that would not show when plugging in regular outlets.
If the GFCI is defective it will trigger even when you plug in Hairdryer.
Inspect the vacuum cable connection to the vacuum, repair or replace.
Comment: I would open up the vacuum first and make sure all thee conductors are attached.  And make sure no junk got inside the canister and is potentially shorting stuff out.


How to calculate break point values and ranges for point density heatmap?

Question: I have some questions about the point density analysis in ArcGIS. I am interested to know the concept and formula about how to come out with all the break point values and ranges of the different colour bands for point density heatmap. I hope any of you can provide me a rough idea about the concept and the formula to use. I want to know the rough Value/Range I can get using the formula.
Answer: You should check the How Hot Spot Analysis (Getis-Ord Gi*) works page of the ArcGIS online help for the formula.
The symbology is based on the Gi_Bin field of the output feature class, see the Hot Spot Analysis (Getis-Ord Gi*) (Spatial Statistics) tool reference page.


Is it possible to chain multiple (more than 2) CouchDB nodes using replicate

Question: Is it possible to replicate multiple nodes of Couch DB by using replicate? In GUI / fauxton to set up replication, there is a local and remote.    can you keep say 4 instances of couch DB in sync across 4 separate datasite locations?
Answer: In your situation, you'll need to set up multiple replications. "Chaining" as a concept does not exist.


Anticipating being offered stock options in a privately held company upon employment. What questions should I ask?

Question: What should I ask about these options? I assume they are worth nothing until (if) the company goes public? Obviously I'll want to judge the relative value so I'll want to know things like outstanding shares (or whatever percentage my offering represents), etc. Any suggestions?
Answer: The company doesn't necessarily have to go public. They can also be worth money if the company is acquired.
Also keep in mind that even if the company does eventually go public, your shares can essentially be wiped out by a round of pre-IPO funding that gives the company a low valuation.
You could ask:

what is the size of the employee pool?
how many classes are outstanding?
was the last round up or down?
what is the mechanism to exercise your options?
can you exercise whenever you want?
Answer: I've had stock options at two different jobs.   If you are not getting a significant ownership stake, but rather just a portion of options as incentive to come work there, I would value them at $0.    If you get the same salary and benefits, but no stock options at another company and you like the other company better, I'd go to the other company.
I say this because there are so many legal changes that seem to take value from you that you might as well not consider the options in your debate.
That being said, the most important question I'd want to know is what incentive does the company have to going public or getting bought?    If the company is majority owned by investors, the stock options are likely to be worth something if you wait long enough.   You are essentially following someone else's bet.    If the company is owned by 2 or 3 individuals who want to make lots of money, they may or may not decide to sell or go public.
Answer: Good questions. I can only add that it may be valuable if the company is bought, they may buy the options. Happened to me in previous company.


Extra tag that would be great if were included

Question: I have recently posted about using a 2-Wire speaker with Arduino Esplora, however I couldn't tag it correctly because there was no arduino-esplora tag. The Esplora tag would be very useful in case anyone posts about an Arduino Esplora, and anyone looking to answer questions about the Arduino Esplora. Thank you for taking the time to read this.
Comment: It seems that an "Arduino-esplora" and "Esplora" tag have been made today. I believe that completes your question. You should accept @NickGammon's answer since it's also right (and the question is resolved).
Answer: A tag should be created (from scratch) if you use it. It doesn't have to exist in advance.
Comment: `It doesn't have to exist in advance.` You need 150 rep for that, though. The OP only has 28.


Getting latest version of software with/without Sourceforge

Question: I want the latest version of software/programs that I have installed on my computer. I figured the best way to do this would be to download the latest one from SourceForge directly rather than via Software Manager.
Questions
a) I was hoping there would be a way that I could simply add the link from SourceForge to the Software Manager (similar to how its done with PPAs) and that way you'd always have the latest version installed every time you do apt update/upgrade. Is there a way to do that?
b) If not, is the only way to get the latest version to use github/git (how exactly do I do this btw? Even a link to a well-answered previous question would be helpful as some I found to be contradicting) and add whatever PPAs I can find to the Software Manager?
c) Also, let's say I still want the version on SourceForge, can I simply create my own PPA and upload the latest versions on there so I can install them later with Software Manager?
Old Version of Question [ignore; left for reference]
When I download and install a software program from Sourceforge, how can I ensure that version remains the latest one? For example, when I install programs via Software Manager, update manager always updates it to the latest version. How would it be able to tell what the latest version of a program installed from Sourceforge is unless I manually visit the Sourceforge site every day and check? (Installing them by downloading their tar.gz packages btw).
Just to clarify, I'm willing to use github (if that applies here?) or whatever other method apart from checking the Sourceforge page myself every time (because that would involve me uninstalling the program and then reinstalling every time an update comes).
I'm on Linux Mint 17.2 if that matters.
Comment: This is what RSS is for...
Comment: Removed a bunch of comments about RSS that got...let's say "snippy"
Comment: What is the problem with a software package manager?
Comment: Thanks all; I rewrote the question so that it's [hopefully!] clearer.
Answer: AFAIK you'll need to check manually if an update is available and, if you want it, manually uninstall the old version and download + install the new one.
It's clearly more cumbersome a process than installing packages via apt-get, which also allows you to easily solve dependencies and do updates.  However, there are a few advantages:

You can compile with your preferred configuration options
You can get not only the latest version but also any other version you choose, from the latest alpha to the more obsolete (DEB packages offer only one version that you can install, and it's not always the most up-to-date)
Since you build the program from source, you can modify it if you feel soinclined
Comment: Thanks for the help; would you mind looking at the new question (b and c, specifically) as I guess I'm gonna have to give up on my SourceForge dream lol...
Comment: _"You always get the latest version"_ - depends on whether the application requirements are met on OP's system. Some apps may need e.g. libX version Y as a minimum requirement and if that version is not available in the repos things get complicated...


LM324 op-amp input current

Question: What is the input current of an op-amp (LM324) if I drive it using 5 V?
Comment: Have you looked for it in the datasheet?
Comment: The input currents of an opamp are not the power supply current. The PNP inputs have positive-going input current of 250nA (0.25uA) maximum. Please show a schematic with its power supply voltage.
Answer: The current drawn by an OpAmp is mostly determined by what it is connected to its output.
If you are looking for a more precise value, you can look at what the datasheet should be referring to as supply current (no load) which is the current the OpAmp draw without driving anything (often in uA)
Comment: When one is being introduced for the first time to a typical datasheet, it's good to point some things out:  1) Datasheets are not immune to typo's and other mistakes.  2) The "Absolute Maximum Ratings" are the limits before damage is done to the chip.  Do not tread near there. 3) Read the whole thing.  The datasheet is the map of your part.  Pay attention to the given units in the tables.  The tables (usually tailored for common power supply values) are super important.  If you see an entry that you do not understand, then use it as an excuse to do some research (and to get more smarter) ;-)
Answer: Usually when we refer to "input current" we mean the current that flows into (or out of) the op-amp inputs.
That's called "bias current" in the datasheet:

Note that these numbers apply for 5V supply voltage. So the "typical" current is -45nA and maximum -250nA at 25°C (some other datasheets indicate -500nA worst-case over the entire temperature range). The negative sign, by convention, indicates current is flowing out of the inputs.
So if we connected the op-amp as follows:

If the initial capacitor voltage is zero, the output will ramp up linearly for about 0.75 second until the op-amp output saturates near 4.0V, indicating the model has a bias current a bit higher than typical for the TI LM324N.
There are a lot of different models and makers of the LM324 and some makers offer low input bias current options such as the TI LM324B which is 10nA typical/35nA maximum at 25°C and 50nA maximum over the entire operating temperature range.

If, by chance, you are referring to the supply current, it is given as follows (here called "quiescent current"):

So at 5V it is typical 0.175mA and maximum 0.3mA. That's per amplifier, so multiply by 4 so 1.2mA maximum total. On top of that we have to add whatever current (if any) that each output is sourcing. For example if each output is at 2.5V and has a 10K resistor to ground that's another 0.25mA each or 1mA total, so 2.2mA would flow into the positive supply pin.

LM324 op-amp input current


Limits and Boundaries of SharePoint Online for Bulk operations

Question: Just want to know what is the Limits and Boundaries of SharePoint Online for Bulk operations. Is there any authentic document I can refer? I am trying to insert 20,000 items with 5 text fields in a batch of 100. sometimes it throws Error "The Operation has timed out" I am using jquery + rest api to perform this bulk operation
Comment: Are you doing this by physically copy and pasting into the list, or are you scripting this?
Comment: I am using JSOM Script
Answer: This does not give you the limits but maybe a solution for your problem.
The bulk limits for SharePoint 2013 is 100 items per operation so i guess it is around that number in Online aswell. SharePoint 2013 Software boundaries

But to resolve your problem try extending the RequestTimeout for your context.
MSDN article explaining RequestTimeout.
But as you are using jQuery and the rest api try setting the timeout property on the ajax call. jQuery ajax documentation
Comment: will try it and revert about the results
Comment: This is the correct answer.  You need to reset the browser threads which are causing the timeout on the browser.  Use the setTimeout(function(){}, 100); to break up the upload.  I would also put some type of modal wait function to lock the page because it will take some time to load everything.
Comment: @VikasSharma did you have any success trying out my suggested answer? Also I have updated my answer with a bit more information.
Comment: For Jquery it did not work.  Tried time out function but sometimes it gives the same error
Answer: Are you doing real bulk requests, or do you make a request per item?
If it is the later, try to schedule your requests and give SP some time. I don't think there are official hard numbers, since there are a lot of relevant factors that are not limited to the service for a timeout to occur.
Had the same problem with general CRUD operations. I would suggest to leave some time between any two requests and don't bulk transfer anything.
(real bulk (batch) requests are possible and shouldn't have this problem. They are available in newer SP installations, but I don't know about their limits. Didn't find a lot of documentation, although that might have been improved.)
Comment: I agreed with your answer. I didn't understand the meaning of real bulk batch ? What do you mean by this ? Synchronous code?
Comment: The "normal" rest operation targets just a single item with a specific itemID. So to update a list with n items, you would have to send n requests. A single bulk request would allow you to create, update or delete n items within a single request. That has the advantage, that there are no further timeouts required. All the payload of the operations for many items is contained in that single request.