Find a random available TCP port — random

Test a series of random TCP ports from 3000 to 8000 (excluding a few that are considered unsafe by Chrome) and return the first available one. A web server can be later started on this port.

random_port(
  port = 4321L,
  host = getOption("servr.host", "127.0.0.1"),
  n = 20,
  exclude = NULL
)

Arguments

port: The preferred port(s).
host: A string that is a valid IPv4 address that is owned by this server, or "0.0.0.0" to listen on all IP addresses.
n: The maximum number of random ports to be tested.
exclude: A vector of port numbers not to be considered.

Value

A port number, or an error if no ports are available.