Nim Socket Server

Sat, 25 Oct 2014 00:00:00 +0000

In learning Nim I decided to implement a trivial Socket server, very small, as an example. Its not a useful HTTP server (it just returns a hard coded HTTP response so we can benchmark it using HTTP tools), and its not async - there are other such examples in the Nim examples directory and in its stdlib. No, I wanted to write a more classical threaded socket server to see how easy that is - especially with the new APIs in Nim “bigbreak” - and see how it performs.

The new “bigbreak” branch that will become Nim 0.10.0 soon-ish has a bunch of new stuff in the networking area. Its replacing the single sockets module with a low level rawsockets module, and a higher level net module. And there is a new selectors module that abstracts over different modern IO polling mechanisms. This means that a single API will use epoll on Linux, kqueue on BSD/OSX, old select on the other Unices and IO Completion ports on Windows. At the moment epoll, select on “other Unices” and IO Completion ports works. kqueue is on the todo.

So without further ado…

Nim wrapping C

Thu, 16 Oct 2014 00:00:00 +0000

Nim has all the language mechanisms needed to smoothly interoperate with C and C++. The rather large collection of wrapped C libraries (and that’s only those in the standard libs) is also a testament to this fact. In this article I explain my personal findings testing out the waters of wrapping a simple C library.

The basic approach to wrapping a simple C library is:

Install Nim.
Install c2nim using Babel or manually clone c2nim from github and build it.
Use c2nim to translate the C header file(s) to a so called Nim wrapper.
Make a small test showing it works.
Write a so called “impure” intermediary library that uses the wrapper (next article)
Make a test green and declare Victory (next article)

Okidoki… (roll up sleeves)

C on Roads Less Taken

Nim Socket Server

Nim wrapping C