function __fish_print_packages

	# apt-cache is much, much faster than rpm, and can do this in real
	# time. We use it if available.

	switch (commandline -tc)
		case '-**'
			return
	end

	#Get the word 'Package' in the current language
	set -l package (_ Package)

	# Set up cache directory
	if test -z "$XDG_CACHE_HOME"
		set XDG_CACHE_HOME $HOME/.cache
	end
	mkdir -m 700 -p $XDG_CACHE_HOME

	if type -q -f apt-cache
		# Do not generate the cache as apparently sometimes this is slow.
		# http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=547550
		apt-cache --no-generate pkgnames (commandline -tc) ^/dev/null | sed -e 's/$/'\t$package'/'
		return
	end

	# Pkg is fast on FreeBSD and provides versioning info which we want for
	# installed packages
	if 	begin
			type -q -f pkg
			and test (uname) = "FreeBSD"
		end
		pkg query "%n-%v"
		return
	end

    # Caches for 5 minutes
	if type -q -f pacman
		set cache_file $XDG_CACHE_HOME/.pac-cache.$USER
		if test -f $cache_file
			cat $cache_file
			set age (math (date +%s) - (stat -c '%Y' $cache_file))
			set max_age 250
			if test $age -lt $max_age
				return
			end
		end

		# prints: <package name>	Package
		pacman -Ssq | sed -e 's/$/\t'$package'/' >$cache_file &
		return
	end

	# Zypper needs caching as it is slow
	if type -q -f zypper
		# If the cache is less than five minutes old, we do not recalculate it

		set -l cache_file $XDG_CACHE_HOME/.zypper-cache.$USER
		if test -f $cache_file
			cat $cache_file
			set -l age (math (date +%s) - (stat -c '%Y' $cache_file))
			set -l max_age 300
			if test $age -lt $max_age
				return
			end
		end

		# Remove package version information from output and pipe into cache file
		zypper --quiet --non-interactive search --type=package | tail -n +4 | sed -E 's/^. \| ((\w|[-_.])+).*/\1\t'$package'/g' > $cache_file &
		return
	end

	# yum is slow, just like rpm, so go to the background
	if type -q -f /usr/share/yum-cli/completion-helper.py

		# If the cache is less than six hours old, we do not recalculate it

		set cache_file $XDG_CACHE_HOME/.yum-cache.$USER
			if test -f $cache_file
			cat $cache_file
			set age (math (date +%s) - (stat -c '%Y' $cache_file))
			set max_age 21600
			if test $age -lt $max_age
				return
			end
		end

		# Remove package version information from output and pipe into cache file
		/usr/share/yum-cli/completion-helper.py list all -d 0 -C | sed "s/\..*/\t$package/" >$cache_file &
		return
	end

	# Rpm is too slow for this job, so we set it up to do completions
	# as a background job and cache the results.

	if type -q -f rpm

		# If the cache is less than five minutes old, we do not recalculate it

		set cache_file $XDG_CACHE_HOME/.rpm-cache.$USER
			if test -f $cache_file
			cat $cache_file
			set age (math (date +%s) - (stat -c '%Y' $cache_file))
			set max_age 250
			if test $age -lt $max_age
				return
			end
		end

		# Remove package version information from output and pipe into cache file
		rpm -qa |sed -e 's/-[^-]*-[^-]*$/\t'$package'/' >$cache_file &
		return
	end

	# This completes the package name from the portage tree.
	# True for installing new packages. Function for printing
	# installed on the system packages is in completions/emerge.fish

	# eix is MUCH faster than emerge so use it if it is available
	if type -q -f eix
		eix --only-names "^"(commandline -tc) | cut -d/ -f2
		return
	else
		# FIXME?  Seems to be broken
		if type -q -f emerge
			emerge -s \^(commandline -tc) |sgrep "^*" |cut -d\  -f3 |cut -d/ -f2
			return
		end
	end

end