ABI change. There is some serious evilness here to work around some
gcc weaknesses. We need to know the sizeof(FILE) manually until __sF
goes away in the next major bump. We have the size for Alpha and i386,
missing is ia64, ppc and sparc* (and i386 with 64 bit longs).
At some point down the track we can change the stdin etc #defines to
stop hard coding the size of FILE into application binaries.
Lots of head scratching and ideas and testing by: green, imp