1#include "stdio_impl.h"
2
3int __towrite(FILE* f) {
4    f->mode |= f->mode - 1;
5    if (f->flags & (F_NOWR)) {
6        f->flags |= F_ERR;
7        return EOF;
8    }
9    /* Clear read buffer (easier than summoning nasal demons) */
10    f->rpos = f->rend = 0;
11
12    /* Activate write through the buffer. */
13    f->wpos = f->wbase = f->buf;
14    f->wend = f->buf + f->buf_size;
15
16    return 0;
17}
18