main

Thin R package that ships C sources for an Emscripten MAIN_MODULE front-end (Rmain). The binary is linked by the r-main conda recipe against libR using cross-r-base Makeconf flags; it is not built as an R SHLIB.

C API

Symbol	Role
rmain_init(argc, argv)	Rf_initEmbeddedR once; sets R_running_as_main_program
rmain_eval(code)	Parse/eval UTF-8 source in R_GlobalEnv via R_tryEval
rmain_last_error()	Message for the most recent rmain_eval failure
extractArchiveFromMemory(data, size)	libarchive extract of an in-memory tarball into the Emscripten FS

JS API (rmain_post.js on the Emscripten Module)

API	Role
initR(args?)	Embedded R init
evalR(code)	Eval UTF-8 R; throws on error
fetchUrls(urls, { concurrency, onProgress, onDone })	Concurrent HTTP GET of archives/assets
extractArchiveFromMemory(Uint8Array)	Untar into the Emscripten FS; throws on failure
populateFilesystem({ metaUrl, packagesBaseUrl, concurrency, onProgress })	Fetch empack_env_meta.json, download each packages[] and mounts[] archive, extract into the FS

populateFilesystem options:

• metaUrl — URL of empack_env_meta.json (default ./empack_env_meta.json)
• packagesBaseUrl — base URL for package filenames (default: directory of metaUrl)
• concurrency — parallel downloads (default 5)
• onProgress({ downloadedBytes, totalBytes, percent }) — download progress callback

Fails if the meta fetch, any archive fetch, or any extract fails.

Layout

• src/ — compiled and installed under $PREFIX/bin/Rmain{,.wasm}
• NAMESPACE — no useDynLib; this package does not install a .so