> Okay, understood. At a later step, we may want to add code for all > suboptimal programs. For now, let me ask a further question: What about > MAXHOSTNAMELEN? If there is no fixed value for this, how can I determine the > value at run time?
This (PATH_MAX) is a case where there is no generic run-time limit either. You can use pathconf/fpathconf to find the limit (if any) on a particular filesystem. If it returns -1, then there is no calculable limit at all.
