> exactly what happens when i type ctrl-c (linux version of 
> httrack), and then answer httrack's question with 'q' 
> (quit),and then continue with 'httrack ... --continue'?
Files stored in cache (or referenced in cache) will be 
reused and not downloaded twice. 

> Will it re-download all pages from scratch (basically 
> ignoring the cache)?
No ; but quitting (not using "interrupt") may loose few 
html files that could have been in the memory