What are the __retarget_lock functions?

[Thomas Kindler]

Hello!

I've been using newlib on an STM32 with FreeRTOS for a few years (using the 
official GNU Arm Embedded Toolchain).

Up until now, I enabled FreeRTOS with configUSE_NEWLIB_REENTRANT, implemented 
the syscalls (_sbrk, _read, _write, etc.) and __malloc_lock / __malloc_unlock.

Now I see, that there are new functions in "lock.h".

Unfortunately, I could not find any information on these functions. A google 
search found a lot of FreeRTOS + newlib projects, but none of them implemented 
these locks.

Do I need to implement them (how?)

Why are they needed and what do they do?


best regards,
-- 
Thomas Kindler <mail+newlib@t-kindler.de>