getxxyyy.c uses the USER environment variable to determine a user
to test getpwnam_r(). If this variable is unset then the test will
seg fault. We work around this issue by defaulting to ``root'' if
USER is not set. This is not perfect as root may not exist on the
system but given that user does exist on most systems, this is the
best default that we can choose if we have no other options available.
