On 10/17/07, Macy Gasp <[EMAIL PROTECTED]> wrote: > On 10/17/07, Andrew Haley <[EMAIL PROTECTED]> wrote: > > Macy Gasp writes: > > > Hi everybody, > > > > Read the Fine Manual: > > > > > > int vsprintf(char *str, const char *format, va_list ap); > > > > The functions vprintf(), vfprintf(), vsprintf(), vsnprintf() > > are equivalent to the functions printf(), fprintf(), sprintf(), > > snprintf(), respectively, except that they are called with a > > va_list instead of a variable number of arguments. These > > functions do not call the va_end macro. C onsequently, the value > > of ap is undefined after the call. The application should call > > va_end(ap) itself afterwards. > > > > > > Andrew. > > > > Thanks for the answer, I missed that part :( . > Thanks to the other Andrew too , for his answer :) >
By the way, I need a suggestion... I want to write a "format_string" function in C++, like this: std::string format_string(const char* format, va_list args); This has an internal static buffer in which I try 1st to vsnprintf(). If it overflows, I dynamically allocate a suitable buffer and try vsnprintf again. The problem is that I'd need to va_copy the args variable in order to re-use it for the second vsnprintf; but this isn't portable on Windows using cl (probably other platforms too)... Any ideas on how I could solve this?
