[PATCH 1/9] cpukit, testsuite: Add rtems_printf and rtems_printer support.

[Chris Johns]

On 23/05/2016 22:37, Gedare Bloom wrote:
> How does this affect user applications?

It should not but if a user has an application that is using the plugin 
interface there is a struct name change. The previous struct ended in 
'_t' and that is reserved for POSIX plus the name included _printk_ and 
it is a plugin interface for printf, printk, fprintf and fiprintf (I 
think). The change for a user is simple and should be stable from here on.

The rtems_printf interface can become a documented interface and we can 
maintain it. The previous interface was functionally fine and is pretty 
much as it was but it's user interface needed some rework, which is what 
I have done. For example there was no easy way to test if a plugin was 
present and if not present dropped all output.

Going forward there is a benefit for small memory devices and there is a 
case for printf possibly mapping to rtems_vprintf for those BSPs. I am 
not yet sure how this would be managed but it could be via SYSINT and 
confdefs.h. Defining a stable way to manage this sort of things removes 
the need for users to handle it in their applications.

Chris