Where can unions and structures be used ?

[naresh850]

Hi,

Can anybody tall me where union can use and where structure can use with example.

 

[dsp4us]

where union can use

Take a look


I don't want to repeat myself.
Cheers.

 

[vinseth]

where union can use

Structure is a method of packing data of different types. A structure is a convenient method of handling a group of related data items of different data types.
example:
struct lib_books
{
char title[20];
char author[15];
int pages;
float price;
};

Union:
Unions like structure contain members whose individual data types may differ from one another. However the members that compose a union all SHARE THE SAME STORAGE AREA within the computers memory where as each member within a structure is assigned its own unique storage area. They are useful for application involving multiple members. Where values need not be assigned to all the members at any one time.

 

[naresh850]

where union can use

con u give me the name of perticuler application for union use

 

[7rots51]

Re: where union can use

variables of same type can be defined in a structure.

Variables of different type that can share the same physical memory can be defined in union.
It is better to read some C text for more details.

 

[btbass]

where union can use

Just look in any header file from the Pic30 tools c compiler for a Pic30, Pic33, Pic24 micro.
Most ports or registers are defined as bit fields and also as ints.
You can clear a port by writing 0 to the int or set individual bits by using the bit fields.
They share memory.
Unions are also good when ram space is limited.
Beware though, they are not fully portable.