7.4.3 Check Whether Literal Uses of long Still Make Sense

A variable that is defined as a long is 32 bits in the ILP32 data-type model and 64 bits in the LP64 data-type model. Where it is possible, avoid problems by redefining the variable and use a more portable derived type.

Related to this, a number of derived types have changed under the LP64 data-type model. For example, pid_t remains a long in the 32-bit environment, but under the 64-bit environment, a pid_t is an int.