FOSDEM is an annual event for software developers, focused on open source software, happening in Bruxelles during the first weekend of February.
The event this year was the 5th FOSDEM conference I attended, starting from 2010. During the years I have seen it evolve: as the presentation focus moved along with the industry, some topics faded out and got replaced by newer things. Many of these newcomers did not actually gain traction over the years and also faded out at some point.
One of the main transitions I have noticed was the one from abstract or too general things (e.g. discussions on the Linux Kernel or performance tricks in C/C++) towards end products and getting (soon to be) mature technologies applied in order to get clear outcomes.
The long interview day is nearing its end. Googamazbook got the best and the worst out of you (well, neither of those, but I’m trying to put some literature in here); the last interviewer comes in, smiles condescendently and greets you with:
Time for the easy interview, heh?
Yes, you have all the reasons to be concerned and feel you’re just one step away from failure (yes, why didn’t you spend the day by the pool in the basement of the many stars hotel they got you a room in for the interview?). But without further ado, the questions start pouring in:
How do you figure out if a process is CPU bound or I/O bound?
Tricky! Let’s not jump to the conclusion. There are 2 variables here, this means we have 4 possibilities:
You’re in a tiny room at Googamazbook and the interviewer comes in, says hi (if you’re lucky), presents themselves (they’re really into doing you a favor) and then starts asking questions. The easy one comes first:
What happens when you run telnet www.brainware.ro 80 ? Please go on through all the layers.
Warmed up from the systems interview, you start talking about /etc/hosts and /etc/resolv.conf: name resolution and then the actual connection to the http port. If your knowledge stops here, please do go on reading this text. Or just do go on, maybe I forgot something.
1. Name Resolution
The name resolution protocol is performed by sending an UDP packet to each resolver found in /etc/resolv.conf. The UDP packet has a small header containing: