Everything requires a C compiler to build and expects an ISO C89 or later
C compiler and libraries.  Presence of strdup is also assumed, which is
guaranteed by POSIX 2008 but common in many earlier C libraries as well.
Otherwise, the files are meant to be copied into packages and the
requirements depend on which files one copies.

A Kerberos library, either MIT Kerberos or Heimdal, is required to build
this package as-is, since the Kerberos portability layer is built and
tested by default.  The other code will run fine without this requirement
when copied into other packages.

PAM libraries and headers are required to build the package as-is, since
the PAM supporting library is built and tested by default.  Other code can
be copied from this package without introducing a PAM dependency.

To build the the kafs portability layer, one of Linux, Mac OS X, Solaris
11, the kafs library that comes with either Heimdal or KTH Kerberos, the
kopenafs library that comes with newer OpenAFS, AFS header files (on any
other platform besides AIX or IRIX), or AFS libraries (on AIX and IRIX) is
required.  AIX binaries with AFS PAG support may not run on AIX systems
that do not have an AFS client installed due to how AIX handles system
calls.

To run the full test suite, and to use the Perl test support libraries,
Perl 5.6.2 or later is required.  The following additional Perl modules
will be used if present:

* IPC::System::Simple
* Test::MinimumVersion
* Test::Perl::Critic
* Test::Pod
* Test::Spelling
* Test::Strict

All are available on CPAN.  Those tests will be skipped if the modules are
not available.
