/rcS.d/README

 1The scripts in this directory whose names begin with an 'S' are
 2executed once when booting the system, even when booting directly into
 3single user mode.
 4
 5The scripts are all symbolic links whose targets are located in
 6/etc/init.d/ .
 7
 8To disable a script in this directory, rename it so that it begins
 9with a 'K' and run 'update-rc.d script defaults' to update the order
10using the script dependencies.
11
12For more information see /etc/init.d/README.