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union

hi, friends this nowsheer , in union can we give function declaration,and how memory aligment for bit fields
thanks & rgds
nowsheer
Nov 24 '07 #1
1 826
weaknessforcats
9,208 Expert Mod 8TB
In C++ you can put a function declaration in a union. The function would be called the same as if it were in a struct or class.

In C you cannot put a function declaration inside a struct. There are no member function in C. Here you would declare a function pointer instesd.

Bit field alignment is up to the compiler. Usually, the compiler aligns on word boundaries. A conputer word is the size of the processor registers. So in 32-bit system, the bit field would be aligned on a 32-bit boundary.

If this is a C++ question, bit fields are not used in C++. Instead, C++ uses the bitset<> template.
Nov 24 '07 #2

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