I must be missing something in the discussion about random
numbers. Why does groff need them? In the offered example
tmp="$d/eqn2graph$groff_rand"
the "random number" serves only to make a (supposedly) unique
name. But of course, if the number is truly random, it is not
guaranteed to be unique. Why does groff not use the time-honored
$$ to serve the purpose? The only requirement for an absolute
guarantee of uniqueness is that the shell script whose pid $$
represents lives as long as the temporary file.
Doug McIlroy
