Are licenses relevant for small code snippets? [closed]

Question

When I'm about to write a short algorithm, I first check in the base class library I'm using whether the algorithm is implemented in it. If not, I often do a quick google search to see if someone has done it before (which is the case, 19 times out of 20).

Most of the time, I find the exact code I need. Sometimes it's clear what license applies to the source code, sometimes not. It may be GPL, LGPL, BSD or whatever. Sometimes people have posted a code snippet on some random forum which solves my problem.

It's clear to me that I can't reuse the code (copy/paste it into my code) without caring about the license if the code is in some way substantial. What is not clear to me is whether I can copy a code snippet containing 5 lines or so without doing a license violation.

Can I copy/paste a 5-line code snippet without caring about the license? What about one-liner? What about 10 lines? Where do I draw the line (no pun intended)?

My second problem is that if I have found a 10-line code snippet which does exactly what I need, but feel that I cannot copy it because it's GPL-licensed and my software isn't, I have already memorized how to implement it so when I go around implementing the same functionality, my code is almost identical to the GPL licensed code I saw a few minutes ago. (In other words, the code was copied to my brain and my brain after that copied it into my source code).

Edit: I'm located in Sweden. It makes me even more confused that this is country-dependent. What if I re-use a piece of code (in a manner which is legal where I live) and I sell this source code to a company in a country where the re-use of code would be illegal.

Answer 1

I am not a lawyer - but i've recently been involved in looking at issues like this. Copying and pasting code from blogs can certainly be considered copyright infringement unless the blog states the license that the code is under and how it can be reused.

I'd recommend using sample code like this only to give you the general process/idea for a solution - then reimplement the idea from your own head and in your own style.

As also suggested, mailing for permission is another alternative. Most people blogging code are open to having it reused.