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#pragma pack directive

hi,
Can any body tell me
#pragma pack directive in visual studio is ISO/ANSI compilant or it is visual studio specific one. If i use this directive the code will be portable or not?

Regards,
Rajesh

I don't know which version of Visual Studio you're using ... but the one I'm familiar with (MSVC++ 5/6) is absolutely not portable.

Most compilers have some equivalent for byte alignment; sometimes pragma's (like MSVC), sometimes compiler options. Here's an example:

Code:

#if defined(WATCOM)

  _Packed

#elif defined(WIN32)

  #pragma pack(push, 1)

#endif

struct o_backup_bowler_rec 

{

  char name[21+1];

  char init[3+1];

  WORD bowler_num;

  BYTE keeping;

#if defined(LINUX)

} __attribute__ ((packed));

#elif defined(WIN32)

};

#pragma pack (pop)

#else

};

#endif

thanks for the reply.
Then i need to see the compiler manual to see what needs to be done for packing.

Regards,
Rajesh