Export file descriptor usage/limit.
Export file descriptor usage/limit.

Skip on not implemented after first error.
gosigar currently only has FDUsage implemented on FreeBSD and Linux.

vaibhavarora/cockroach,petermattis/cockroach,maxlang/cockroach,cockroachdb/cockroach,maxlang/cockroach,paperstreet/cockroach,maxlang/cockroach,veteranlu/cockroach,glycerine/cockroach,paperstreet/cockroach,paperstreet/cockroach,veteranlu/cockroach,cockroachdb/cockroach,maxlang/cockroach,petermattis/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,veteranlu/cockroach,glycerine/cockroach,vaibhavarora/cockroach,petermattis/cockroach,glycerine/cockroach,paperstreet/cockroach,cockroachdb/cockroach,petermattis/cockroach,maxlang/cockroach,paperstreet/cockroach,cockroachdb/cockroach,vaibhavarora/cockroach,petermattis/cockroach,vaibhavarora/cockroach,glycerine/cockroach,petermattis/cockroach,veteranlu/cockroach,maxlang/cockroach,veteranlu/cockroach,paperstreet/cockroach,paperstreet/cockroach,maxlang/cockroach,glycerine/cockroach,vaibhavarora/cockroach,vaibhavarora/cockroach,glycerine/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,petermattis/cockroach,maxlang/cockroach,paperstreet/cockroach,glycerine/cockroach,glycerine/cockroach,cockroachdb/cockroach,veteranlu/cockroach,petermattis/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,cockroachdb/cockroach