shlib: Compile shared library
In richfitz/rcmdshlib: Build Shared Libraries From R

Description Usage Arguments Value Author(s) Examples

Compile a shared library using R CMD SHLIB. Options exist for converting the compiler output to R messages, warnings and errors.

shlib(filenames, verbose = TRUE, output = NULL, clean = FALSE,
  preclean = FALSE, dry_run = FALSE, debug = FALSE,
  stop_on_error = TRUE, warn_on_warning = TRUE, chdir = FALSE,
  use_colour = NULL)

`filenames`	Vector of filenames
`verbose`	Be verbose (print compiler output to screen)
`output`	Name to use for the file output (passed to `SHLIB` with `--output` – by default the name of the first file is used with the extension changed to `.Platform$dynlib.ext`).
`clean`	Clean intermediate targets (passed to `SHLIB` as `--clean`)
`preclean`	Clean intermediate targets before running (passed to `SHLIB` as `--clean`)
`dry_run`	Don't run anything, but print commands (passed to `SHLIB` as `--dry-run`)
`debug`	Create a debug dll (windows only; passed to `SHLIB` as `--debug`)
`stop_on_error`	If an error in compilation is thrown, throw an error (TRUE by default). If set to `FALSE`, then the compilation output will be returned (the `dll` element will be set to `NA`).
`warn_on_warning`	If a the compiler returns a warning, issue an R warning (TRUE by default).
`chdir`	One of `FALSE` (the default) indicating that the working directory will not be changed, `TRUE` indicating that the working directory should be set to the directory containing source files, or a character string indicating the directory to set immediately prior to compilation. If `TRUE`, then all files listed in `filenames` must be in the same directory.
`use_colour`	Use ANSI escape colours (via the `crayon` package) if on a ANSI compatibile terminal (does not support Rstudio, Rgui or Rterm). If `NULL` (the default) then colour will be used where support is detected by `crayon::has_color()`

Invisibly, A list with four elements: success - a logical indicating if the command was successful (this can only be FALSE if stop_on_error is FALSE), output - an object of class compiler_output containing compiler output, dll - the path to the created shared library, or NA_character_ if the command failed, and base - the dll name without leading path or extension (suitable to use as the PACKAGE argument to .Call). If the command changed directory then the normalized (and therefore absolute) path to the dll is returned.

Rich FitzJohn

# A small piece of C code saved as add.c within a temporary directory:
txt <- c("#include <R.h>",
        "#include <Rinternals.h>",
        "SEXP add2(SEXP a, SEXP b) {",
        "  return ScalarReal(REAL(a)[0] + REAL(b)[0]);",
        "}")
path <- tempfile()
dir.create(path)
filename <- file.path(path, "add.c")
writeLines(txt, filename)

# Compile the object:
res <- rcmdshlib::shlib(filename)
res

# Load it into R:
dyn.load(res$dll)

# And call it
.Call("add2", pi, 1, PACKAGE = res$base)
# Cleanup
dyn.unload(res$dll)
unlink(path, recursive = TRUE)