i dont find it unreasonable to write full perl programs that make no assumptions about what systems they run on whatsoever... actually, that's one of its real strengths and the reason many commercial applications and many inhouse tools were written in it. it can bridge systems flawlessly because it has its own library of functions.

there are multiple CPAN modules for uptime/load, i had a look at some of them. there are a couple of reasons why i would prefer not to use them:

1. they have no corresponding packages in most operating systems (only the most used/famous ones have) and would create overhead in system admininstration.
2. they use exactly the same unportable techniques like using sysctl and /proc and so on