Re: Receive a pointer to a struct from an external function ?

[Benoît Minisini <benoit.minisini@xxxxxxxxxxxxxxxx>]

Le 15/02/2026 à 22:10, Lee a écrit :
> While working with Libc, I encountered an issue when receiving a pointer 
> to a structure from an external function.
>
> The C structure contains members which are declared as "char *". I 
> declared the Gambas structure with those members "As String". But, 
> attempting to print the string values causes a Segmentation Fault.
>
> If those very members are declared "As Pointer", using String@ to print 
> the values works.
>
> Is this a bug in the external interface, an unrealistic expectation on 
> my part, or something I am doing incorrectly?
>
> Project attached.

Inside a Gambas structure, a String is a Gambas string, and only Gambas 
can create it. So if you use it to store a C string (a 'char *'), you 
need to use a Pointer.

It's only for function argument and function return value that you can 
use the Gambas String datatype, provided that you use it correctly as 
explained in the wiki.

In other words, you really need to know how C works to understand what 
you can do, and how you can do it in all cases.

Regards,

--
Benoît Minisini.