Often, if you need to know which files are accessed during the startup of an application, you are stuck searching for them in the manpage. Also, probably not all of them are documented there.
I use strace to find these files:
strace -efile /usr/bin/program 2>&1 1>/dev/null | grep ^open | cut -d\" -f2
Note that unless you place the grep expression in between this will
give you all syscalls that involve files, i.e. also simple checks
whether a file exists or has a certain permission set.