+pi() { # package install
+ local s f
+ if dpkg -s -- "$@" &> /dev/null; then
+ return 0;
+ fi;
+ while fuser /var/lib/dpkg/lock &>/dev/null; do sleep 1; done
+ f=/var/cache/apt/pkgcache.bin;
+ if [[ ! -r $f ]] || (( $(( $(date +%s) - $(stat -c %Y $f ) )) > 60*60*12 )); then
+ apt-get update
+ fi
+ apt-get -y install --purge --auto-remove "$@"
+}