ARM Cortex-M Microcontroller startup files

[Jens Bauer via Digitalmars-d]

On Thursday, 30 April 2015 at 20:54:07 UTC, Martin Nowak wrote:
> On 04/30/2015 08:43 AM, Timo Sintonen wrote:
>> Printf is a little tricky. It is actually a file operation to 
>> stdout and that is actually a syscall to kernel.
>
> No, you usually have to implement some hook for outputting 
> yourself, e.g. putc or write, printf solely takes care of the 
> formatting.

My knowledge isn't really deep here, but doesn't printf call 
vfprintf(stdout, ...) and
vfprintf call vsnprintf followed by fwrite, etc. ?

Thus I would expect the hook to be somewhere in vfprintf ?