ref: d9eeaec45f1f206922711c3dcd6787be15aaefe7
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; }