Before proceeding to read the rest of this document, it should be noted that the text assumes that certain files are placed in certain directories. Where they have been specified, the conventions we adopt here for locating these files are those of the relevant RFC (RFC-86.0, see bibliography). If you are using a distribution of Linux (or some other operating system) that supports PAM but chooses to distribute these files in a diferent way you should be careful when copying examples directly from the text.
As an example of the above, where it is explicit, the text assumes
that PAM loadable object files (the modules) are to be located in
the following directory: /lib/security/. This is generally
the location that seems to be compatible with the Linux File System
Standard (the FSSTND). On Solaris, which has its own licensed version
of PAM, and some other implementations of UN*X, these files can be
found in /usr/lib/security. Please be careful to perform the
necessary transcription when using the examples from the text.