Thanks for all the replies.

I must admit, I had overlooked using the template or suffix options that File::Temp offers by default.

I do have calls to rand in other parts of the code (and calls to File::Temp prior to the fork()s), but I was just a little surprised that exactly the same sequences were occurring across so many processes.

dws suggests that calling srand in each child will re-seed the rand function - I'll give that one a shot too, although I did find the warning in the perldoc for 5.6.1 a little concerning:

Do not call srand multiple times in your program unless you know exactly what you're doing and why you're doing it.

Cheers,

BazB.