GNAT pragma IMPORT and type conversions

GNAT pragma IMPORT and type conversions

[mcnett michael david]

In my current project, I am using the GNAT Ada package and interfacing 
(pragma IMPORT) with the C language.  I can do the interfaces well and
send/receive variables, but I am not sure about how the language converts
from ada types (integer, array, access, etc.) to C types (unsigned long,
unsigned long long, pointers, etc.).  Also, what about subtypes and 
enumerated types.  I imagine it looks at the base class in the conversion.

Are there any example programs out there that deal with this problem? If
so, where are they?

Thanks in advance,

______________________________________________________________
Michael McNett               |
Graduate Student             |
University of Illinois       |
mmcnett@uiuc                 |

Re: GNAT pragma IMPORT and type conversions

[Tom Griest]

In article <mmcnett.781382539@sparc53.cs.uiuc.edu> mmcnett@sparc53.cs.uiuc.edu (mcnett michael david) writes:
>
>In my current project, I am using the GNAT Ada package and interfacing 
>(pragma IMPORT) with the C language.  I can do the interfaces well and
>send/receive variables, but I am not sure about how the language converts
>from ada types (integer, array, access, etc.) to C types (unsigned long,
>unsigned long long, pointers, etc.).  Also, what about subtypes and 
>enumerated types.  I imagine it looks at the base class in the conversion.
>
>Are there any example programs out there that deal with this problem? If
>so, where are they?
>
>Thanks in advance,
>
>______________________________________________________________
>Michael McNett               |
>Graduate Student             |
>University of Illinois       |
>mmcnett@uiuc                 |
>
>
>

Re: GNAT pragma IMPORT and type conversions

[Robert Dewar]

The conversion from Ada types to C types in the GNAT environment is
quite canonical. FOr example integer always corresponds to int, and
system.unsigned_types.unsigned always corresponds to the C unsigned type.

The GNAT documentation is certainly not very complete in this area, I will
try to have it updated a bit in this particular area for the next release.

Meanwhile, if you have specific questions, address them to gnat-report
as usual.

Re: GNAT pragma IMPORT and type conversions

[Robert Dewar]

please send questions to gnat-report, we will bne happy to help you out.