+# Prints the current OS. Supported are Debian (debian) and Mac OS X (darwin)
+# at the moment. If an unsupported OS is used an error is printed.
+os() {
+ if [ -f /etc/debian_version ]; then
+ echo debian
+ elif [ x`uname` = xDarwin ]; then
+ echo darwin
+ else
+ echo unsupported OS! >&2
+ return 1
+ fi
+}
+