Re: Size and pack

[Vincent Smeets <Vincent.Smeets@CCI.Sema.de>]

Adrian Hoe wrote:
> 
> Hello,
> 
> I have the following declaration:
> 
>    type Rx_Header_Data is
>       record
>          Start_Byte   : Character := Latin_1.STX;
>          Splitter     : Character;
>          Command_Byte : Character;
>          Pad_Byte_1   : Character;
>          Pad_Byte_2   : Character;
>          Log_Num      : Interfaces.C.Long;
>          End_Byte     : Character := Latin_1.ETX;
>          LRC          : Character;
>       end record;
> 
> It supposed to be 11 bytes long but Rx_Header_Data'Size reports 14
> bytes. 'Size will report 11 bytes when I add the following line:
> 
> pragma pack (Rx_Header_Data);
> 
> I have found that Log_Num : Interfaces.C.Long takes up 7 bytes without
> pragma pack.

Just an other view and a question to CLA,

If you read and write this record thrue a stream, will you then get the
correct byte layout (with Log_Num at an odd byte)?

-- 

Vincent Smeets
SchlumbergerSema -
Competence Center Informatik GmbH 
Lohberg 10 - 49716 Meppen - Germany
 tel: +49 5931-805-461
 fax: +49 5931-805-175
mail: VSmeets@slb.com
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