.aliases: Add ifactive

This lists only the active network interfaces. Handy for quickly chopping down the wall-of-text that is `ifconfig`.

Credit to g.rocket over at https://unix.stackexchange.com/a/108048/6040.

Closes mathiasbynens#722.

.aliases

@@ -61,6 +61,9 @@ alias ip="dig +short myip.opendns.com @resolver1.opendns.com"
 alias localip="ipconfig getifaddr en0"
 alias ips="ifconfig -a | grep -o 'inet6\? \(addr:\)\?\s\?\(\(\([0-9]\+\.\)\{3\}[0-9]\+\)\|[a-fA-F0-9:]\+\)' | awk '{ sub(/inet6? (addr:)? ?/, \"\"); print }'"
 
+# Show active network interfaces
+alias ifactive="ifconfig | pcregrep -M -o '^[^\t:]+:([^\n]|\n\t)*status: active'"
+
 # Flush Directory Service cache
 alias flush="dscacheutil -flushcache && killall -HUP mDNSResponder"