“As a user of an Alpha processor running Linux I often face
the problem of trying to get code to work on it which works fine on
the x86 boxes most people are using. Often these programs use
constructs which just don’t work on 64 bit processors. While this
might currently annoy a few nutty Alpha and SPARC users, the IA64
is about to land and mean that 64 bit systems become a bit more
common. In this document I try and list some of the common
things you have to be careful of to make sure that your code is 64
bit clean.“
“64 bit Linux machine use an organisation called LP64 where
‘long’s and pointers are 64 bit in length but everything else is 32
bit; long long’s are also 64 bit. 32 bit Linux systems have both
long’s and pointers as 32 bit and have the ‘long long’ type as 64
bit.”