REENT_SMALL

Jeff Johnston jjohnstn@redhat.com
Fri Nov 28 17:51:00 GMT 2008


Raphael Derosso Pereira wrote:
> Hello,
>
> I would like to know what is the size difference between the normal
> reent structure and the small reent structure?
>
> Best Regards,
>
> --
> Raphael Derosso Pereira
> Engenheiro de Computação
> icq: 4517421
> msn: rderossopereira@hotmail.com
> Skype: rderossopereira
>   
To figure it out, just print sizeof(struct _reent) with one of the 
standard headers included.  Then do it again with  #define _REENT_SMALL 
defined at the top.

The normal reent structure is currently 1120 bytes and the small version 
is 240 bytes to start.
The _REENT_SMALL version grows dynamically as features are used and due 
to this there is often an
extra level of indirection accessing fields.  It really is meant for 
extremely small platforms with little memory to spare.

-- Jeff J.



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