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From: Thomas Martitz <thomas.martitz@student.HTW-Berlin.de>
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Am 19.12.2009 16:35, schrieb Gene Creighton:
>
> typedef struct
> {
>     short  ImageFileType;
>     long   FileSize;
>     short  Reserved1;
>     short  Reserved2;
>     long   ImageDataOffset;
> } WIN3XHEAD;
>
> typedef struct
> {
>     long   HeaderSize;
>     long   ImageWidth;
>     long   ImageHeight;
>     short  NumberOfImagePlanes;
>     short  BitsPerPixel;
>     long   CompressionMethod;
>     long   SizeOfBitmap;
>     long   HorzResolution;
>     long   VertResolution;
>     long   NumColorsUsed;
>     long   NumSignificantColors;
> } WIN3XINFOHEAD;
>
>
> ----------
>


Try appending __attribute__((packed)) after the closing } of the structs 
in question. That should disable padding.

Furthermore I recommend using int32_t instead of long, since long is 8 
bytes on 64-bit Linux systems (hence your code wouldn't work on those).

Best regards.