It is possible to write software that solves real business problems, cheaply and reliably. The recipe is well known, even though it's not easy to do.
I am an Extreme Programmer. I help individuals, teams and organization become more effective. I'm lucky to work as a developer for ThoughtWorks, mostly in the Milano area. I used to teach at Università dell'Insubria.
An operation is "thread-safe" if it can be performed from multiple threads safely, even if the calls happen simultaneously on multiple threads.
An operation is re-entrant if it can be performed while the operation is already in progress (perhaps in another context). This is a stronger concept than thread-safety, because the second attempt to perform the operation can even come from within the same thread.
Raymond Chen