netstat

netstat allows you to easily view which TCP ports are in use and which are free to use.

# install.packages("netstat")
library(netstat)

See which TCP ports are currently in use with ports_in_use()

ports_in_use()

##  [1]   137   138  1024  5353  5432  9947 11090 12113 12441 13445 13675 18588
## [13] 21946 29434 30402 39333 49153 49154 49155 49156 49157 50038 50869 51223
## [25] 51225 51226 51233 51238 51281 51282 51285 51286 51287 51497 51882 52366
## [37] 52874 52953 52977 53026 53072 53253 53470 54258 54709 55143 55342 55878
## [49] 56063 56109 56340 56365 56566 56607 56699 56729 56730 56743 56752 56753
## [61] 56755 56758 56766 56852 56853 56854 56859 56860 56864 56870 56876 56877
## [73] 56878 56898 56907 56924 57182 57863 57958 57987 58939 59344 59457 60289
## [85] 60873 61825 61932 62589 63035 63561 64543 64720

Find a free TCP port using free_port()

free_port()

## [1] 14415

• free_port() returns an available TCP port from Internet Assigned Numbers Authority (IANA) listed unassigned ports.

• free_port() will not return any TCP port currently in use - so free_port() can safely be used to allocate a ports programmatically without collisions - great for automated testing or browser automation in general