Re: Safe to maintain pointer to errno() ?

On 10/14/2010 1:34 PM, Dennis Lovelady wrote:

W.r.t the "why fight it" question, I'm inclined to agree. But since some of
our jobs process a few million rows at a time, and for each row there can be
significant errno testing, the insignificance of the pointer retrieval might
add up to measurable values.

I can't say for sure, but I don't think there are very many functions that require errno to be set to zero before calling the function. In most cases, the errno pointer only has to be fetched when the function reported failure through some other mechanism like its return code. I'm guessing that usually you'd be calling the __errno function approximately zero times per record.