aau-vlc-annotated.sh

	# This is the actual filename that will be installed once the app is installed
	# note that the '.app' suffix _is_ included because we might be
	# installing preference panes so we don't want to assume.
INSTALLED_NAME="VLC.app"

	# this is the directory where the 'INSTALLED_NAME' program will go
	# when it is installed. Could be anywhere as long as user can write to it
	# such as "$HOME/Applications" or "$HOME/Library/PreferencePanes"
	# or even something weird like '/var/mac/apps' if you have a truly
	# odd configuration for some reason.
INSTALL_DIR="/Applications"

	# DL_URL _must_ be compatible with `curl --location --remote-name`
	# Also, it _must_ be _one line_ although I have put it on several
	# lines for readability in this example. A user should be able to
	# run `fgrep DL_URL=` on this file and get the full command
	# necessary for getting the URL
DL_URL=$(curl -sL 'http://update.videolan.org/vlc/sparkle/vlc.xml' |\
	awk -F'"' '/http:\/\/.*\.dmg/{print $2}'|\
	tail -1)

	# This is actually optional _IFF_ the end of DL_URL is the same
	# as the filename. For example, this:
	# 	http://www.omnigroup.com/download/latest/omnifocus
	# when used with `curl --location --remote-name` is going to leave
	# us with a file named 'omnifocus' which isn't what we want, so
	# in that case we'd want to define
	# 	FILENAME=omnifocus.dmg
	# OTOH:
	# http://www.omnigroup.com/ftp1/pub/software/MacOSX/10.6/OmniFocus-1.10.6.dmg
	# would leave us with 'OmniFocus-1.10.6.dmg'
	# which would work just fine, and in that case we would not need a
	# FILENAME= line at all

# OPTIONAL IF: "$DL_URL:t"
# REQUIRED IF: not equal to "$DL_URL:t"
FILENAME="$DL_URL:t"

	# Like DL_URL this should all be on one line. A user should be able to run
	# `fgrep LATEST_VERSION=` on this file and get the full command.
	# how do
LATEST_VERSION=$(curl -sL 'http://update.videolan.org/vlc/sparkle/vlc.xml' |\
	awk -F'"' '/sparkle:version/{print $2}'|\
	tail -1)

	# If the app we are going to install is already installed, we need to know what
	# to check the LATEST_VERSION against to see if the app is up to date
	# This is usually CFBundleShortVersionString or CFBundleVersion
	# The main script will check in
	# $INSTALL_DIR/$INSTALLED_NAME/Contents/Info.plist
	# (there's also a few other edge cases but those are the most common)
VERSION_TYPE="CFBundleVersion"

	# need to know this for trying to resume partial downloads, checking
	# download size, etc.
	# Most servers support this, but some do not, so if this is not defined
	# it will be assumed to be 'yes' but it's better to explicitly define it
	# if possible
# OPTIONAL IF: answer is 'yes'
# REQUIRED IF: answer is 'no
DOES_SERVER_SUPPORT_HEAD="yes"