How to quickly startup/shutdown Oracle 11?

I am wondering what is the quickest way to properly startup/shutdown a Oracle DB daemon (Oracle 11.2, installed on a test machine).

I need it for C/C++ programs that use the OCI/Pro*C API.

Currently I script it like this – startup:

sqlplus /nolog <<EOF
connect / as sysdba
startup
quit
EOF
lsnrctl start
emctl start dbconsole

And shutdown:

emctl stop dbconsole
lsnrctl stop
sqlplus /nolog <<EOF
connect / as sysdba
shutdown
quit
EOF

This works – programs work as expected – but this procedure is quite slow.

The Oracle DB runs on CentOS 6.3, it is the free (as-in-beer) available ‘standard version’.