Creating an integer variable of a certain size

Question

I want to define an integer variable in C / C ++ so that my integer can store 10 bytes of data or maybe x bytes of data that I defined in the program. for now..! I tried

int *ptr;
ptr = (int *)malloc(10);

the code. Now, if I find sizeof ptr, it displays as 4, not 10. Why?

Answer 1

The C and C ++ compilers implement several sizes of integers (usually 1, 2, 4, and 8 bytes {8, 16, 32, and 64 bits}), but without any auxiliary code for the preliminary arithmetic operation, you cannot arbitrary size integers numbers.

Statements you made:

int *ptr;
ptr = (int *)malloc(10);

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Answer 2

4 . , ptr int *. sizeof, malloc new , sizeof - , , .

Answer 3

4 , 4 . , 10 . , :

struct VariableInteger
{
    int *ptr;
    size_t size;
};

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Answer 4

4. - :

typedef struct
{
    int a[10];
} big_int_t;

big_int_t x;

printf("%d\n", sizeof(x));

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Answer 5

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Answer 6

10- . , , <limits.h>, , , .

Answer 7

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Here is a link to a list of arithmetic libraries of arbitrary accuracy in several different languages, Wikipedia compliments: link .