Forum OpenACS Development: Re: Image resizing, exec and server problems
As long as it works for you and you tested (with a minimum effort) that it scales (to whatever extent) than it is apparently fine (at least).
However, another critical thing is the kind of exec call itself (redirector, background, ...) and the code surrounding it. Malte never posted the critical exec line, at least to my knowledge.
In other words, if it works for you. Go ahead!
My option referred more to use a non-blocking variant and link it to the background delivery feature (a larger picture of design).
I agree while there are resources on comp.lang.tcl etc. that report on the threaded fork() issue, I cannot find a concise statement on the issue's state (fixed, open, unsolvable).