issetugid on MacOS & *BSD #4722
Description
Is a simple fn() -> c_int syscall available on all flavours of BSD. Allows checking if a process is setuid/setgid 'tainted'.
This system call exists so that library routines (eg: libc, libtermcap)
can reliably determine if it is safe to use information that was ob-
tained from the user, in particular the results from getenv(3) should
be viewed with suspicion if it is used to control operation.