Packed Strcutures in GCC

Friend · **Posted:** Fri Oct 25, 2002 11:26 am

Hi,

I need to know how I can create a packed structure in GCC, ie. it only has as many bytes as needed.

thanks.

Okiesmokie · **Posted:** Fri Oct 25, 2002 2:04 pm

typedef struct {
/* Code here */
} __attribute__((packed));

sonneveld · **Posted:** Fri Oct 25, 2002 5:20 pm

make sure you're not using this packed structure to read in data from a file.. cause it's very iffy. you're better off just reading in each byte to make sure you have the correct endian.

- Nick

Friend · **Posted:** Fri Oct 25, 2002 8:45 pm

With this would I put the name of the structure before __attribute__ ((packed)) like below?

typedef struct {
/* Code here */
} struct_name __attribute__((packed));

thanks.

Okiesmokie · **Posted:** Sat Oct 26, 2002 11:20 am

I dont think it really matters, i put my struct names after the __attribute__((packed))

Tim · **Posted:** Wed Oct 30, 2002 7:54 am

Also, this seems to work on both gcc and the Microsoft compiler:

Code:

#pragma pack(push, 1) /* use 1, 2, 4, etc. */
struct your_structure
{
};
#pragma pack(pop)

OSDev.org

Packed Strcutures in GCC

Who is online