ref: e60e6dc4ded6d0ff578610e39d7a8c8a6f62f3ed
dir: /src/libc/stdio/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.flags = _IORW | _IOSTRG;
f.len = siz;
f.buf = s;
f.wp = s;
f.rp = s + siz;
r = vfprintf(&f, fmt, ap);
if (s) {
if (f.wp == f.rp)
--f.wp;
*f.wp = '\0';
}
return r;
}