title: Why does R system() commands to kill port processes also kill Ubuntu 19.10 Rstudio session?
body: <p>System commands to kill port processes also kill my Rstudio session on ubuntu 19.10. On my system if I do the following, I crash my RSTUDIO session:</p>
  
  <pre><code>#IN RSTUDIO RUNNING LINE BY LINE
  library(RSelenium)
  rD1 &lt;- rsDriver(browser="chrome",port=4567L, chromever = "79.0.3945.36")
  system("kill -9 $(lsof -t -i:4567)")
  Sys.sleep(1)
  </code></pre>
  
  <p>Session Info:</p>
  
  <pre><code>&gt; sessionInfo()
  R version 3.6.1 (2019-07-05)
  Platform: x86_64-pc-linux-gnu (64-bit)
  Running under: Ubuntu 19.10
  
  Matrix products: default
  BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.8.0
  LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.8.0
  
  locale:
   [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
   [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8    LC_PAPER=en_US.UTF-8       LC_NAME=C                 
   [9] LC_ADDRESS=C               LC_TELEPHONE=C             LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  
  loaded via a namespace (and not attached):
   [1] RSelenium_1.7.5  compiler_3.6.1   assertthat_0.2.1 tools_3.6.1      wdman_0.2.4      binman_0.1.1     Rcpp_1.0.3      
   [8] caTools_1.17.1.3 openssl_1.4.1    bitops_1.0-6     semver_0.2.0     XML_3.98-1.20    askpass_1.1
  </code></pre>