ref: c35217a1a61f795d312eede2f84faf59c7c06a3c
dir: /lib/c/vsnprintf.c/
#include <stdarg.h>
#include <stdio.h>
#undef vsnprintf
int
vsnprintf(char * restrict s, size_t siz, const char * restrict fmt, va_list ap)
{
FILE f;
int r;
f.flag = _IOWRT | _IOSTRG;
f.size = siz;
f.buf = s;
f.wp = s;
f.rp = s + siz;
r = vfprintf(&f, fmt, va);
if (s) {
if (f.wp == f.rp)
--f.wp;
*f.wp = '\0';
}
return r;
}