Update modification time of a file (touch)

Question

How do I touch a file (i.e., update its modification time without changing its contents) in R? I'm looking for a cross-platform built-in (or packaged) equivalent of:

system2("touch", file_name)

Answer 1

I have found an implementation in the R.utils package, it utilizes the same pattern as suggested by @thelatemail but also offers vectorization and a fallback for R < 2.14, and invisibly returns the old timestamp:

R.utils::touchFile(file_name)

As usual, library(sos); ???touch was invaluable for finding this.