Count the number of lines in a file without reading entire file into memory?

Question

I\'m processing huge data files (millions of lines each).

Before I start processing I\'d like to get a count of the number of lines in the file, so I can then indic

Answer 1

using ruby:

file=File.open("path-to-file","r")
file.readlines.size

39 milliseconds faster then wc -l on a 325.477 lines file