Connect to a website via HTTP in C

I have some C code that parses a file and generates another file of processed开发者_运维问答 data. I now need to post these files to a website on a web server. I guess there is a way to do a HTTP POST but I have never done this in c (using GCC on Ubuntu). Does anyone know how to do this? I need a starting point as I have no clue of doing this in C. I also need to be able to authenticate with the website.

libcurl is probably a good place to start.

I think Hank Gay's suggestion of using a library to handle the details is the best one, but if you want to "do it yourself", you need to open a socket to the web server and then send your data in the HTTP POST format which is described here. Authentication can mean a variety of different things, so you need to be more specific.

Unfortunately, all of the above three jobs involve a fair bit of complexity, so you need to break the question down into stages and come back and ask about each bit separately.