Re: Free-ing memory: not springing leaks?

[chris <spamoff.danx@ntlworld.com>]

Matthew Heaney wrote:

 > chris.danx wrote:
>>For example, the library loader for linux error mechanism is to return
>>an error msg describing the problem.  Once you have it appears to be
>>your problem what you do with it.  There is no call present in the
>>library to return the memory.
> 
> This is an Ada binding?  Who wrote it?

No it is a C library for loading libraries at runtime.  Its' error 
handling returns errors as strings (customised to the library & call 
made) - though it'd be easier if it was ints, the errors can be for a 
variety of reasons but you need to parse them to handle them effectively!

const char *dlerror(void);

I wrote a binding to it, but did not know at the time free-ing C memory 
from Ada (with Interfaces.C.Strings.Free) was a no-no.  The binding 
takes the error message, converts it to an Ada string, free's the memory 
of the C string (with Interfaces.C.Strings.Free) and raises an exception 
tagged with the Ada String.

I will change this soon to use the native C compilers/libs "Free" (I 
forgot this when making the initial post.  I have free'd c memory from 
ada before).


> If you know it was malloc'd, then yes, just write a binding to free and
> call that.

And if you don't, then it's hit and miss? ... it figures.   I wonder how 
C programmers deal with this :(


Thanks for your help, it's much appreciated.


Chris