localhost-alias

#!/bin/bash
# -----------------------------------------------------------------------------
#          FILE:  localhost-alias
#   DESCRIPTION:  Adds/removes localhost aliases.
#        AUTHOR:  Sorin Ionescu <sorin.ionescu@gmail.com>
#       VERSION:  1.0.0
# -----------------------------------------------------------------------------


if [[ $1 && $1 == "add" ]] 
then
	if [[ $2 ]] 
	then
		sudo dscl localhost -create "/Local/Default/Hosts/$2" IPAddress 127.0.0.1
		sudo dscacheutil -flushcache
		echo "Hostname $2 now points to localhost."
	else
		echo "ERROR: You have to specify a valid hostname alias to add."
	fi
	exit
fi

if [[ $1 && $1 == "remove" ]] 
then
	if [[ $2 ]] 
	then
		sudo dscl localhost -delete "/Local/Default/Hosts/$2"
		echo "Hostname $2 no longer points to localhost."
	else
		echo "ERROR: You have to specify a valid hostname alias to remove."
	fi
	exit
fi

if [[ $1 && $1 == "list" ]] 
then
	dscl localhost -list "/Local/Default/Hosts"
	exit
fi

if [[ $1 && $1 == "cache" ]] 
then
	dscacheutil -cachedump -entries Host
	exit
fi

echo "usage: $(basename $0) <command> [hostname]"
echo
echo "The available commands are:"
echo "  add       Adds or updates a hostname."
echo "  remove    Removes a hostname."
echo "  list      Lists available hostname."
echo "  cache     Dumps the cached hostnames."