Utilities for converting files in R documentation (Rd) format to other formats or create indices from them, and for converting documentation in other formats to Rd format.
R CMD Rdconv [options] file
R CMD Rd2pdf [options] filesthe path to a file to be processed.
a list of file names specifying the R documentation sources to use, by either giving the paths to the files, or the path to a directory with the sources of a package.
further options to control the processing, or for obtaining information about usage and version of the utility.
R CMD Rdconv converts Rd format to plain text, HTML or LaTeX
  formats: it can also extract the examples.
R CMD Rd2pdf is the user-level program for producing PDF output
  from Rd sources.  It will make use of the environment variables
  R_PAPERSIZE (set by R CMD, with a default set when R
  was installed: values for R_PAPERSIZE are a4,
  letter, legal and executive)
  R_PAPERSIZE (default a4, also legal and
  executive)
  and R_PDFVIEWER (the PDF previewer).  Also,
  RD2PDF_INPUTENC can be set to inputenx to make use of the
  LaTeX package of that name rather than inputenc: this might be
  needed for better support of the UTF-8 encoding.
R CMD Rd2pdf calls tools::texi2pdf to produce
  its PDF file: see its help for the possibilities for the
  texi2dvi command which that function uses (and which can be
  overridden by setting environment variable R_TEXI2DVICMD).
Use R CMD foo --help to obtain usage information on utility
  foo.
The chapter “Processing Rd format” in the “Writing R Extensions” manual.