third_party/ulib/musl/src/stdio/__towrite.c

#include "stdio_impl.h"

int __towrite(FILE* f) {
    f->mode |= f->mode - 1;
    if (f->flags & (F_NOWR)) {
        f->flags |= F_ERR;
        return EOF;
    }
    /* Clear read buffer (easier than summoning nasal demons) */
    f->rpos = f->rend = 0;

    /* Activate write through the buffer. */
    f->wpos = f->wbase = f->buf;
    f->wend = f->buf + f->buf_size;

    return 0;
}