How can I decode a RAW/WAV file into a list of numbers?

How can I decode a RAW/WAV file into a list of numbers ?

I need to do since I need to create a spectrogram/waveform from the audio file.

I thought I could use the list of numbers and create an image using a charting application (e.g. gnuplot)

A raw files usually don't need any decoding, since it is already a list of numbers (hence 'raw').

Wav file is also a list of numbers, but with a header with extra information (number of channels, sampling rate, etc.). You don't mention what environment/programming language you use (which might help other people to help you), but if it is c/c++ you can use http://www.mega-nerd.com/libsndfile/