$conf['savedir'] = '/app/www/public/data';
if [ "$(id -u)" != 0]; then sudo "$0" "$*" exit $? fi
Section 2.6.2 of the documentation
Expansion can differ depending on parameter value and set status and possibly assign.
Substitution can also provide string length and prefix/suffix patterns.
7z a -t7z [OUTPUT FILE].7z -m0=lzma2 -mx=9 [INPUT FILE]