[PATCH][BZ #12847] dprintf/vdprintf can cause fork to fail (child process crash)

[Roland McGrath]

> There are plenty of cases where the underlying printf code uses malloc if 
> it needs an allocation too large for alloca (and the cut-off, or how such 
> allocations relate to the arguments passed to dprintf, is not as far as I 
> know considered a public interface to glibc).

This was not the case at the time.  dprintf predates the complex printf
features like $ and wide-char support and so on.