Re: how to use lmem.h ?

[Bertrand Mansion <lua@...>]

On Sat, Feb 21, 2009 at 7:34 PM, Irayo <irayo.lt@irayo.net> wrote:
>
> On Feb 21, 2009, at 10:29 AM, Bertrand Mansion wrote:
>
>>
>>
>> Is there something wrong with this code ?
>> Also, is there something wrong in using malloc/free in Lua modules ?
>
>
> At first glance I see nothing wrong with the code, but it's been a while
> since I've dealt with this.
>
> The reason for using lua_getallocf() instead of malloc/free is so that the
> Lua user's allocation function is used.  The user can define an allocator
> that is more efficient for their operating system (esp. embedded systems
> which might have small amounts of memory), and this allocator might not use
> malloc/free or might malloc/free larger chunks at once to prevent memory
> fragmentation.  By using lua_getallocf you can take advantage of those
> things.
>
> In addition, running out of memory using the user's allocator function
> causes Lua to throw an out-of-memory error, which is catchable by pcall,
> etc.  malloc/free would not normally do this without further programming.
>
> (Lua's allocator function can be overwritten by the C API or by other
> modules with lua_setallocf.)

Thank you for this explanation :)