v3.5.0

• You can now append environment variables to the ones set in the current
  process if you include "current" in the value of env, in run()
  and for process$new(): env = c("current", NEW = "newvalue") (#232).

• Sub-processes can now inherit the standard input, output and error from
  the main R process, by setting the corresponding argument to an empty
  string. E.g. run("ls", stdout = "") (#72).

• run() is now much faster with large standard output or standard
  error (#286).

• run() can now discard the standard output and error or redirect
  them to file(s), instead of collecting them.

• processx now optionally uses the cli package to color error messages
  and stack traces, instead of crayon.