[zwegner]

Ah, thanks for the references. Now that you mention them, I realize I definitely knew about tup and fabricate before (and possibly waf?), but had forgotten about them. I haven't really thought much about trace-based build systems in years, until this subthread.

And looking through that waf blog post, I realize that I meant ptrace instead of strace--I want full fine-grained syscall interception, not just a text report afterwards. That gets around a lot of the overhead/parsing problems mentioned, and is required for the "pause build command so its input file can be built" case.