Caleb Epstein wrote:
On Sat, 23 Oct 2004 07:10:48 +0000 (UTC), Darryl Green <darryl.green@unitab.com.au> wrote:
char buf[101]; va_list args; va_start(args, fmt); int n = vsnprintf (buf, 101, fmt, args)); va_end(args); if (n < 0) return;
This is one of the reasons I find the *snprintf functions to be pure evil. They don't return -1 when the output would be too long, they return the size they WOULD have written if the buffer was large enough.
That's not evil; it's extremely useful if you want to dynamically allocate a large enough buffer. All you have to do is check that the return value is less than or equal to the length you passed in. (Aside: what if the length is greater than INT_MAX?)
Is this code doing what you intend?
When built with Visual C++, it probably is. MS documents this function as returning a negative value in case of error. A portable test would be size_t(n) > sizeof(buf). Ben.