newlib syscall stubs

[RaAl_264636]

Hi,

       

I want to realize the newlib syscall stubs. I know that they're delivered pre-compiled, but if own implementations are provided, those implementations will be used.

   

Has anyone experience with implementing those stubs? The newlib documentation https://sourceware.org/newlib/libc.html#Syscalls shows the minimum implementations. However, if I use them as a base without modification, some errors are thrown. For example, the sbrk() function uses 'stack_ptr', but it's not stated where this variable is defined. Do I have to replace this with the stack pointer for the target device, register R13 in case of Cortex-M processors?

   

So, the question is how to implement the stubs correctly for PSoC.

       

Regards,

       

Ralf

[JobinT_31 · Accepted solution]

Hi Ralf,

   

You will be able to find some information in these below links. I don't think any one here have done this already:

   

https://www.gnu.org/software/libc/manual/html_node/Porting.html

   

http://forum.osdev.org/viewtopic.php?t=27073&p=226666

       

Thanks

   

JOBIN GT

[RaAl_264636]

Hi Jobin,

       

thank you for those links, I'll read through them.

       

Regards,

       

Ralf