MFC revs. 1.50 - 1.52: prevents statistics displayed by SIGINFO handler from overflow, avoid division by zero, place error checking code near to the syscall, style.
MFC revs. 1.50 - 1.52: prevents statistics displayed by SIGINFO
handler from overflow, avoid division by zero, place error checking
code near to the syscall, style.

Approved by:	re (bmah)

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase