Category Archives: Development

daniel weekly 41, now in markdown

Episode 41, just out:


me on kodsnack

115 days with RFC

http2 explained in markdown, translations. Swedish?

The curl google tech talk

curl -X

the curl and wget war

curl vs Wget

a curl cheat sheet

curl feature freeze period, release october 7

ApacheCon, October 2

Bug of the week: Downloading a long sequence of URLs results in high CPU usage and slowness

Option of the week: -O

Yours truly on “kodsnack”

kodsnackKodsnack is a Swedish-speaking weekly podcast with a small team of web/app- developers discussing their experiences and thoughts on and around software development.

I was invited to participate a week ago or so, and I had a great time. Not surprisingly, the topics at hand moved a lot around curl, Firefox and HTTP/2. The recorded episode has now gone live, today.

You can find kodsnack episode 120 here, and again, it is all Swedish.

One year and 6.76 million key-presses later

I’ve been running a keylogger on my main Linux box for exactly one year now. The keylogger logs every key-press – its scan code together with a time stamp. This now allows me to do some analyses and statistics of what a year worth of using a keyboard means.

This keyboard being logged is attached to my primary work machine as well as it being my primary spare time code input device. Sometimes I travel and sometimes I take time-off (so called vacation) and then I usually carry my laptop with me instead which I don’t log and which uses a different keyboard layout anyway so merging a log from such a different machine would probably skew the results a bit too much.

Func KB-460 keyboard

What did I learn?

A full year of use meant 6.76 million keys were pressed. I’ve used the keyboard 8.4% on weekends. I used the keyboard at least once on 298 days during the year.

When I’m active, I average on 2186 keys pressed per hour (active meaning that at least one key was pressed during that hour), but the most fierce keyboard-bashing I’ve done during a whole hour was when I recorded 8842 key-presses on June 9th 2015 between 23:00 and 24:00! That day was actually also the most active single day during the year with 63757 keys used.

In total, I was active on the keyboard 35% of the time (looking at active hours). 35% of the time equals about 59 hours per week, on average. I logged 19% keyboard active minutes, minutes in which I hit at least one key. I’m pretty amazed by that number as it equals almost 32 hours a week with really active keyboard action.

Zooming in and looking at single minutes, the most active minute occurred 15:48 on November 10th 2014 when I managed to hit 405 keys. Average minutes when I am active I type 65 keys/minute.

Looking at usage distribution over week days: Tuesday is my most active day with 19.7% of all keys. Followed by Thursday (19.1%), Monday (18.7%), Wednesday (17.4%) and Friday (16.6%). I already mentioned weekends, and I use the keyboard 4.8% on Sundays and a mere 3.6% on Saturdays.

Separating the time-stamps over the hours of the day, the winning hour is quite surprising the 23-00 hour with 11.9% followed by the more expected 09-10 (10.0%), 10-11 and 14-15. Counting the most active minutes over the day shows an even more interesting table. All the top 10 most active minutes are between 23-00!

The most commonly pressed keys are: space (10%) and backspace (6.5%) followed by e, t, a, s, left control, i, cursor down, o, cursor up, n, r. 29 keys were pressed more than 1% of the times. 30 keys were pressed less than 0.01%. I used 99 different keys over the year (I believe my keyboard has 105 keys).

Never pressed keys? All 6 of the never touched keys are in the numpad: 2, 3, 5, 6, 9 and the comma/del key.

I’ll let the keylogger run and see what else I’ll learn over time…

My first year at Mozilla

January 13th 2014 I started my fiMozilla dinosaur head logorst day at Mozilla. One year ago exactly today.

It still feels like it was just a very short while ago and I keep having this sense of being a beginner at the company, in the source tree and all over.

One year of networking code work that really at least during periods has not progressed as quickly as I would’ve wished for, and I’ve had some really hair-tearing problems and challenges that have taken me sweat and tears to get through. But I am getting through and I’m enjoying every (oh well, let’s say almost every) moment.

During the year I’ve had the chance to meetup with my team mates twice (in Paris and in Portland) and I’ve managed to attend one IETF (in London) and two special HTTP2 design meetings (in London and NYC). counts 47 commits by me in Firefox and that feels like counting high. bugzilla has tracked activity by me in 107 bug reports through the year.

I’ve barely started. I’ll spend the next year as well improving Firefox networking, hopefully with a higher turnout this year. (I don’t mean to make this sound as if Firefox networking is just me, I’m just speaking for my particular part of the networking team and effort and I let the others speak for themselves!)

Onwards and upwards!

Coverity scan defect density: 0.00

A couple of days ago I decided to stop slacking and grab this long dangling item in my TODO list: run the coverity scan on a recent curl build again.

Among the static analyzers, coverity does in fact stand out as the very best one I can use. We run clang-analyzer against curl every night and it hasn’t report any problems at all in a while. This time I got almost 50 new issues reported by Coverity.

To put it shortly, a little less than half of them were issues done on purpose: for example we got several reports on ignored return codes we really don’t care about and there were several reports on dead code for code that are conditionally built on other platforms than the one I used to do this with.

But there were a whole range of legitimate issues. Nothing really major popped up but a range of tiny flaws that were good to polish away and smooth out. Clearly this is an exercise worth repeating every now and then.

End result

21 new curl commits that mention Coverity. Coverity now says “defect density: 0.00” for curl and libcurl since it doesn’t report any more flaws. (That’s the number of flaws found per thousand lines of source code.)

Want to see?

I can’t seem to make all the issues publicly accessible, but if you do want to check them out in person just click over to the curl project page at coverity and “request more access” and I’ll grant you view access, no questions asked. week #3

I won’t keep posting every video update here, but I mostly wanted to mention that I’ve kept posting a weekly video over at youtube basically explaining what’s going on right now within my dearest projects. Mostly curl and some Firefox stuff.

This week: libcurl server cert verification API got a bashing at SEC-T, is HTTP for UDP a good idea? How about adding HTTP cache support to libcurl? HTTP/2 is getting deployed as we speak. Interesting curl bug when used by XBMC. The patch series for Firefox bug 939318 is improving slowly – will it ever land?

Snaxx delivers

A pint of guinnessLate in the year 1999 I quit my job. I handed over a signed paper where I wrote that I quit and then I started my new job first thing in the year 2000. I had a bunch of friends at the work I left and together with my closest friends (who coincidentally also switched jobs at roughly the same time) we decided we needed a way to keep in touch with friends that isn’t associated with our current employer.

The fix, the “employer independent” social thing to help us keep in touch with friends and colleagues in the industry, started on the last of February 2000. The 29th of February, since it was a leap year and that fact alone is a subject that itself must’ve been discussed at that meetup.

Snaxx was born.

Snaxx is getting a bunch of friends to a pub somewhere in Stockholm. Preferably a pub with lots of great beers and a sensible sound situation. That means as little music as possible and certainly no TVs or anything. We keep doing them at a pace of two or three per year or so.

Bishops Arms logo

Yesterday we had the 31st Snaxx and just under 30 guests showed up (that might actually have been the new all time high). We had many great beers, food and we argued over bug reporting, discussed source code formats, electric car charging, C64 nostalgia, mentioned Linux kernel debugging methods, how to transition from Erlang to javascript development and a whole load of other similarly very important topics. The Bishops Arms just happens to be a brand of pubs here that have a really sensible view on how to run pubs to be suitable for our events so yesterday we once again visited one of their places.

Thanks for a great time yesterday, friends! I’ll be setting up a date for number 32 soon. I figure it’ll be in the January 2015 time frame…If you want to get notified with an email, sign up yourself on the snaxx mailing list.

A few pictures from yesterday can be found on the Snaxx-31 G+ event page.

My home setup

I work in my home office which is upstairs in my house, perhaps 20 steps from my kitchen and the coffee refill. I have a largish desk with room for a number of computers. The photo below shows the three meter beauty. My two kids have their two machines on the left side while I use the right side of it for my desktop and laptop.

Daniel's home office

Many computers

The kids use my old desktop computer with a 20″ Dell screen and my old 15.6″ dual-core Asus laptop. My wife has her laptop downstairs and we have a permanent computer installed underneath the TV for media (an Asus VivoPC).

My desktop computer

I’m primarily developing C and C++ code and I’m frequently compiling rather large projects – repeatedly. I use a desktop machine for my ordinary development, equipped with a fairly powerful 3.5GHz quad-core Core-I7 CPU, I have my OS, my home dir and all source code put on an SSD. I have a larger HDD for larger and slower content. With ccache and friends, this baby can build Firefox really fast. I put my machine together from parts myself as I couldn’t find a suitable one focused on horse power but yet a “normal” 2D graphics card that works Fractal Designfine with Linux. I use a Radeon HD 5450 based ASUS card, which works fine with fully open source drivers.

I have two basic 24 inch LCD monitors (Benq and Dell) both using 1920×1200 resolution. I like having lots of windows up, nothing runs full-screen. I use KDE as desktop and I edit everything in Emacs. Firefox is my primary browser. I don’t shut down this machine, it runs a few simple servers for private purposes.

My machines (and my kids’) all run Debian Linux, typically of the unstable flavor allowing me to get new code reasonably fast.

Func KB-460 keyboardMy desktop keyboard is a Func KB-460, mechanical keyboard with some funky extra candy such as red backlight and two USB ports. Both my keyboard and my mouse are wired, not wireless, to take away the need for batteries or recharging etc in this environment. My mouse is a basic and old Logitech MX 310.

I have a crufty old USB headset with a mic, that works fine for hangouts and listening to music when the rest of the family is home. I have Logitech webcam thing sitting on the screen too, but I hardly ever use it for anything.

When on the move

I need to sometimes move around and work from other places. Going to conferences or even our regular Mozilla work weeks. Hence I also have a laptop that is powerful enough to build Firefox is a sane amount of time. I have Lenovo Thinkpad w540a Lenovo Thinkpad W540 with a 2.7GHz quad-core Core-I7, 16GB of RAM and 512GB of SSD. It has the most annoying touch pad on it. I don’t’ like that it doesn’t have the explicit buttons so for example both-clicking (to simulate a middle-click) like when pasting text in X11 is virtually impossible.

On this machine I also run a VM with win7 installed and associated development environment so I can build and debug Firefox for Windows on it.

I have a second portable. A small and lightweight netbook, an Eeepc S101, 10.1″ that I’ve been using when I go and just do presentations at places but recently I’ve started to simply use my primary laptop even for those occasions – primarily because it is too slow to do anything else on.

I do video conferences a couple of times a week and we use Vidyo for that. Its Linux client is shaky to say the least, so I tend to use my Nexus 7 tablet for it since the Vidyo app at least works decently on that. It also allows me to quite easily change location when it turns necessary, which it sometimes does since my meetings tend to occur in the evenings and then there’s also varying amounts of “family activities” going on!


For backup, I have a Synology NAS equipped with 2TB of disk in a RAIDSynology DS211j stashed downstairs, on the wired in-house gigabit ethernet. I run an rsync job every night that syncs the important stuff to the NAS and I run a second rsync that also mirrors relevant data over to a friends house just in case something terribly bad would go down. My NAS backup has already saved me really good at least once.


HP Officejet 8500ANext to the NAS downstairs is the house printer, also attached to the gigabit even if it has a wifi interface of its own. I just like increasing reliability to have the “fixed services” in the house on wired network.

The printer also has scanning capability which actually has come handy several times. The thing works nicely from my Linux machines as well as my wife’s windows laptop.


fiber cableI have fiber going directly into my house. It is still “just” a 100/100 connection in the other end of the fiber since at the time I installed this they didn’t yet have equipment to deliver beyond 100 megabit in my area. I’m sure I’ll upgrade this to something more impressive in the future but this is a pretty snappy connection already. I also have just a few milliseconds latency to my primary servers.

Having the fast uplink is perfect for doing good remote backups.

Router  and wifi

dlink DIR 635I have a lowly D-Link DIR 635 router and wifi access point providing wifi for the 2.4GHz and 5GHz bands and gigabit speed on the wired side. It was dead cheap it just works. It NATs my traffic and port forwards some ports through to my desktop machine.

The router itself can also update the dyndns info which ultimately allows me to use a fixed name to my home machine even without a fixed ip.

Frequent Wifi users in the household include my wife’s laptop, the TV computer and all our phones and tablets.


Ping Communication Voice Catcher 201EWhen I installed the fiber I gave up the copper connection to my home and since then I use IP telephony for the “land line”. Basically a little box that translates IP to old phone tech and I keep using my old DECT phone. We basically only have our parents that still call this number and it has been useful to have the kids use this for outgoing calls up until they’ve gotten their own mobile phones to use.

It doesn’t cost very much, but the usage is dropping over time so I guess we’ll just give it up one of these days.

Mobile phones and tablets

I have a Nexus 5 as my daily phone. I also have a Nexus 7 and Nexus 10 that tend to be used by the kids mostly.

I have two Firefox OS devices for development/work.

I’m with Firefox OS!


I have received a Firefox OS tablet as part of a development program. My plan is to use this device to try out stuff I work on and see how it behaves on Firefox OS “for real” instead of just in emulators or on other systems. While Firefox OS is a product of my employer Mozilla, I personally don’t work particularly much with Firefox OS specifically. I work on networking in general for Firefox, and large chunks of the networking stack is used in both the ordinary Firefox browser like on desktops as well as in Firefox OS. I hope to polish and improve networking on Firefox OS too over time.

Firefox OS tablet


The primary development device for Firefox OS is right now apparently the Flame phone, and I have one of these too now in my possession. I took a few photos when I unpacked it and crammed them into the same image, click it for higher res:

Flame - Firefox OS phone

A brief explanation of Firefox OS

Firefox OS is an Android kernel (including drivers etc) and a bionic libc – simply the libc that Android uses. Linux-wise and slightly simplified, it runs a single application full-screen: Firefox, which then can run individual Firefox-apps that appears as apps on the phone. This means that the underlying fundamentals are shared with Android, while the layers over that are Firefox and then a world of HTML and javascript. Thus most of the network stack used for Firefox – that I work with – the http, ftp, dns, cookies and so forth is shared between Firefox for desktop and Firefox for Android and Firefox OS.

Firefox OS is made to use a small footprint to allow cheaper smartphones than Android itself can. Hence it is targeted to developing nations and continents.

Both my devices came with Firefox OS version 1.3 pre-installed.

The phone

The specs: Qualcomm Snapdragon 1.2GHZ dual-core processor, 4.5-inch 854×480 pixel screen, five-megapixel rear camera with auto-focus and flash, two-megapixel front-facing camera. Dual-SIM 3G, 8GB of onboard memory with a microSD slot, and a 1800 mAh capacity battery.

The Flame phone should be snappy enough although at times it seems to take a moment too long to populate a newly shown screen with icons etc. The screen surface is somehow not as smooth as my Nexus devices (we have the 4,5,7,10 nexuses in the house), leaving me with a constant feeling the screen isn’t cleaned.

Its dual-sim support is something that seems ideal for traveling etc to be able to use my home sim for incoming calls but use a local sim for data and outgoing calls… I’ve never had a phone featuring that before. I’ve purchased a prepaid SIM-card to use with this phone as my secondary device.

Some Good

I like the feel of the tablet. It feels like a solid and sturdy 10″ tablet, just like it should. I think the design language of Firefox OS for a newbie such as myself is pleasing and good-looking. The quad-core 1GHz thing is certainly fast enough CPU-wise to eat most of what you can throw at it.

These are really good devices to do web browsing on as the browser is a highly capable and fast browser.

Mapping: while of course there’s Google maps app, using the openstreetmap map is great on the device and Google maps in the browser is also a perfectly decent way to view maps. Using openstreetmap also of course has the added bonus that it feels great to see your own edits in your own neck of the woods!

I really appreciate that Mozilla pushes for new, more and better standardized APIs to enable all of this to get done in web applications. To me, this is one of the major benefits with Firefox OS. It benefits all of us who use the web.

Some Bad

Firefox OS feels highly US-centric (which greatly surprised me, seeing the primary markets for Firefox OS are certainly not in the US). As a Swede, I of course want my calendar to show Monday as the first day of the week. No can do. I want my digital clock to show me the time using 24 hour format (the am/pm scheme only confuses me). No can do. Tiny teeny details in the grand scheme of things, yes, but annoying. Possibly I’m just stupid and didn’t find how to switch these settings, but I did look for them on both my devices.

The actual Firefox OS system feels like a scaled-down Android where all apps are simpler and less fancy than Android. There’s a Facebook “app” for it that shows Facebook looking much crappier than it usually does in a browser or in the Android app – although on the phone it looked much better than on the tablet for some reason that I don’t understand.

I managed to get the device to sync my contacts from Google (even with my google 2-factor auth activated) but trying to sync my Facebook contacts just gave me a very strange error window in spite of repeated attempts, but again that worked on my phone!

I really miss a proper back button! Without it, we end up in this handicapped iphone-like world where each app has to provide a back button in its own UI or I have to hit the home button – which doesn’t just go back one step.

The tablet supports a gesture, pull up from the button of the screen, to get to the home screen while the phone doesn’t support that but instead has a dedicated home button which if pressed a long time shows up cards with all currently running apps. I’m not even sure how to do that latter operation on the tablet as it doesn’t’ have a home button.

The gmail web interface and experience is not very good on either of the devices.

Building Firefox OS

I’ve only just started this venture and dipped my toes in that water. All code is there in the open and you build it all with open tools. I might get back on this topic later if I get the urge to ventilate something from it… :-) I didn’t find any proper device specific setup for the tablet, but maybe I just don’t know its proper code word and I’ve only given it a quick glance so far. I’ll do my first builds and installs for the phone. Any day now!


My seven year old son immediately found at least one game on my dev phone (he actually found the market and downloaded it all by himself the first time he tried the device) that he really likes and now he wants to borrow this from time to time to play that game – in competition with the android phones and tablets we have here already. A pretty good sign I’d say.

Firefox OS is already a complete and competent phone operating system and app ecosystem. If you’re not coming from Android or Iphone it is a step up from everything else. If you do come from Android or Iphone I think you have to accept that this is meant for the lower end spectrum of smart-phones.

I think the smart-phone world can use more competition and Firefox OS brings exactly that.


Me in numbers, today

Number of followers on twitter: 1,302

Number of commits during the last 365 days at github: 686

Number of publicly visible open source commits counted by openhub: 36,769

Number of questions I’ve answered on stackoverflow: 403

Number of connections on LinkedIn: 608

Number of days I’ve committed something in the curl project: 2,869

Number of commits by me, merged into Mozilla Firefox: 9

Number of blog posts on, including this: 734

Number of friends on Facebook: 150

Number of open source projects I’ve contributed to, openhub again: 35

Number of followers on Google+: 557

Number of tweets: 5,491

Number of mails sent to curl mailing lists: 21,989

TOTAL life achievement: 71,602