How to determine how many bytes are occupied in the C language

In the C language, it can be usedsizeofoperator to determine the number of bytes occupied by any type (including primitive data types, structs, unions, and so on) or variables. sizeofis a built-in operator in the C language, not a function, that calculates the storage size of the specified type or variable at compile time and returns onesize_tThe value of the type, which indicates the number of bytes occupied.

Here are some of the usessizeofAn example of an operator that shows how to check the number of bytes occupied by different types and variables in C:

#include int main() printf("size of struct: %zu bytes", sizeof(struct mystruct));return 0;}

sizeofOperators can be used for type names such assizeof(int)) and variable names (e.gsizeof(myvariable)

sizeofThe size is calculated at compile time, so its operands are not evaluated or executed (which means you can use it safely.)sizeofwithout worrying about raising the *** of operands

In some platforms and compilers, different data types may have different sizes. For example,sizeof(int)It may be 4 bytes on some systems and 2 bytes or 8 bytes on others.

usesizeofOperators are the standard way to check how much storage space a data type or variable occupies in the C language. This is especially important for cross-platform development, optimizing memory usage, and working with binary data.