NetStat fails on *NIX with older versions of lsof

[cljohnso]

NetStat parsing of lsof output depends on the inclusion of the f (file descriptor) field as the first field of a "file" line. Newer versions of lsof include the f field regardless of its designation in the -F option value; older versions only include the f field when the f value is provided in the -F option argument. (This is contrary to lsof documentation but ...) The current version of NetStat does not include the f value in the -F option argument so parsing of the output from older versions of lsof fails.

Fortunately, inclusion of the f value in the -F option is tolerated by newer versions of lsof so the f value needs to be included in the -F option argument to normalize the output over more versions of lsof.

[cljohnso]

This is an observed difference between lsof version 4.91 running on a Mac and lsof version 4.87 running on Centos 7.9.