tfFollow already assigns its argument, so don't do it again

tfFollow shouldn't assign its argument. this should be explicit
in the calling code.
add glibc feature test macros

These should probably be done in a better way, without
feature test macros.
don't pass the long value if it's ReallyBig
make sure no typedefs are redefined
removed trivial assignment
exitFailure() doesn't take any arguments