Solaris 64-bit Developer's Guide

libkstat Kernel Statistics

The sizes of many kernel statistics are completely independent of whether the kernel is a 64-bit or 32-bit program. The data types exported by named kstats (see kstat(3KSTAT)) are self-describing, and export signed or unsigned, 32-bit or 64-bit counter data, appropriately tagged. Thus, applications using libkstat need not be made into 64-bit applications to work successfully with the 64-bit kernel.

Note –

If you are modifying a device driver that creates and maintains named kstats, you should try to keep the size of the statistics you export invariant between 32-bit and 64-bit kernels by using the fixed-width statistic types.