There are many packages for such scenarios. listings, lslisting, fancyvrb, and algorithm I use fancyvrb for listing occasions and would recommend this, but you need to figure it out by yourself whether it really suits you. Also consider possible usage of \begin{VerbatimInput} \end{VerbatimInput} which gives you more freedom. With the numbering and box capabilities, your problem may be solved when crossing pages. Here is a hint: http://tex.stackexchange.com/questions/103536/label-for-package-fancyvrb to use fancyvrb, you need its manual that is readily available. Yes, google search fancyvrb.