[OT] waitpid()

[Lars Hecking]

 Sorry for this OTish post, but I figured the list has excellent
 expertise in this area ...

 I need to implement a configure check for waitpid(). While this by
 itself is trivial, are there any known abnormalities/non-POSIXisms
 I need to consider? Also, are there any concrete examples of operating
 systems (still in use :) that have no waitpid()? Stevens mentions
 pre-SVR4 and pre-BSD4.3.

 Thanks.