Posts Tagged ‘cut’

2012w25

Sunday, June 24th, 2012

Quite a while since I wrote a post now, I’ve not been sick or anything, but there has been a lot of work abound, and outside work I prioritized sleeping over writing. But now I’m back for the moment, so let’s get down to business :)

Since last time I’ve come up with new ways of abusing awk, such as having it find the highest value from a command outputting in the following syntax:

\t<characters, integers, fullstop>: <integer>\n

To make it a little more different, the command also spits out a header, as well as an additional newline after the end of output.

I just now, while writing this, came up with a different solution, which doesn’t use awk:

theCommand | grep -v '^[^ \t]\+' | tr -d ' ' | cut -d':' -f2 | sort -r | head -n 1

but what I ended up using was:

theCommand | awk 'BEGIN { highest = 0 } $0 ~ /^[ \t]/ { if ( $2 > highest ) { highest = $2 } } END { print highest }'

In this case, from what I can gather, awk is the more efficient solution. One process versus five.

Update: As Werner points out, the if statement isn’t really necessary (which also makes it possible to cut out the BEGIN statement as well):

theCommand | awk '/^[^ \t]/ && $2 > highest { highest = $2 } END { printf "%d\n", highest }'

Utilities

  • ditaa (a.k.a DIagrams Through Ascii Art) makes it easy to generate nice-looking diagram images from… rather nice-looking ASCII diagrams
  • docopt, a command-line interface description language, which also seems to support generating the parser for the CLI being described
  • Peity for generating different types of charts using jQuery and <canvas>
  • Ghost.py interacting with web pages, programmatically

As of late I have been thinking a great deal about backups and the project which seems the most interesting to me is Duplicity.

Random tech stuff

Other random not-so-techy stuff

What I pass for humour

:wq

2012w18

Sunday, May 6th, 2012

The scripty stuff

This week I finally managed to crack a problem I’d been trying to solve for a couple of weeks, namely how to only print the foobar errors, and the ensuing stack trace of these errors from a logfile:

awk 'BEGIN { section = 0 } /foobar/ { section = 1; print; next } /^[A-Z]/ && section == 1 { section = 0; next } section == 1 { print; next }' logfile 

Looking at the solution, I am kindof ashamed that it took me that long to get a workable solution…

I also found this neat little oneliner in a comment on reddit: echo "something long and space separated of which you want the last word" | rev | cut -d ' ' -f 1 | rev. Then again, I’m sure that awk could have done this with a little $(NF-1) magic or something like that.

The headache-inducing stuff

All since my netbook broke down, I’ve thought about two things: restoring the netbook/replacing it, and how to create some form of backup infrastructure which should be better than what I have in place today.

As for the backups, the “system” I have today is couple of USB-disks which I at times plug in and sync files to. That and most of my projects and config-files are in various git repositories all synced to the laptop/server-in-the-wardrobe which I made sure to backup after the netbook died, especially since the laptop/server disk is much older than the netbook disk was.

Another thing which bothers me with the current solution is that I have no off-site storage. And that would be nice to have. Belt AND suspenders of course, and off-site storage comes with its own set of problems such as trust in the offsite storage maintainer.

I think the solution will take the shape of a GNU+Linux box and Unison and possibly aided by incron. Not sure yet, will have to think more about it.

There are some other requirements which I have just barely scratched the surface of or not even begun thinking about yet, for instance it would be nice to be able to backup my parents stuff as well on a regular basis as to keep their stuff safer as well.

And as for the netbook, although it was a nice little machine, the keyboard was getting a bit worn out, and at times it was rather underpowered with its single core 1.6GHz atom processor, so the direction I am looking in now is towards something like this.

The stuff screwing over society

Now there’s truly no way in hell I’ll ever use Skype again.

Nothing new under the sun I guess, but it lends credibility to the Skype quip above.

This sure is some level-A grade retarded society we are constructing for ourselves…

Samsung Galaxy S3: The first smartphone designed entirely by lawyers, a great read about a truly depressing matter which probably is closer to the truth than we imagine. On the other hand, my personal opinion is that the midnight blue version looks pretty damn sweet.

SaaS and other crap where someone else is in control sure is a honking good idea, isn’t? Well, I guess it is if you’re the one in control, but I guess you won’t ever get my business…

The cool stuff

And I also managed to find some posts which touched the hacker in me, such as this post about how one could go about generating pseudo-random numbers (don’t use the algorithms, just be inspired by them) or how this guy started shaving bytes off of his “hello, world!” binary.

I immediately thought about FSCONS when I read this, and I didn’t feel at all worried about people thinking the same about our conf :)

Until the other day, when I read about its inclusion into git, I’d never even heard about git subtree, but this post makes a compelling case for looking into it.

I also came across a, to me, new data structure: the XOR linked list. Now, it has a couple of drawbacks, and I don’t think I’ll find much use for it, ever, but as a concept it is a very interesting idea, and just goes to show that XOR is frakking awesome.

I thought this was a pretty cool thing.

While I don’t have any problems with my ISP hijacking DNS requests right now, it is nice to know for posterity that there are ways around it ;)

If you are going to use JSON, and need comments, this seems like a reasonable way to go about it.

While I haven’t decided what I think about Go I really liked this blog post on how to create a grass mowing agent which derives the most optimal way to cut the digital grass in a simulated world.

Hopefully I ain’t the only one who finds this hilarious ;)

This is actually quite neat: Instead of adding “lorem ipsum” paragraphs all over your design, tweak the word list in the script, include it in the mockup, and markup all places which need filler content. Done.

In the latest issue of DatorMagaZin there was an article about FUSE which caught my eye, and having read the article my interest was piqued, so I just had to go look at the list myself, and truly, have you seen all the cool filesystems people have come up with? Frakkin’ awesome!

The food for thought stuff

Oh yeah, finally remember to treat everyone the way you’d like people to treat your own mother

:wq