What's the difference between size_t and int in C++?

c++ c types int
tunnuz picture tunnuz · Feb 2, 2009 · Viewed 130.1k times · Source

In several C++ examples I see a use of the type size_t where I would have used a simple int. What's the difference, and why size_t should be better?

Answer

Joao da Silva picture Joao da Silva · Feb 2, 2009

From the friendly Wikipedia:

The stdlib.h and stddef.h header files define a datatype called size_t which is used to represent the size of an object. Library functions that take sizes expect them to be of type size_t, and the sizeof operator evaluates to size_t.

The actual type of size_t is platform-dependent; a common mistake is to assume size_t is the same as unsigned int, which can lead to programming errors, particularly as 64-bit architectures become more prevalent.

Also, check Why size_t matters

Related questions

C/C++ use of int or unsigned int

In a lot of code examples, source code, libraries etc. I see the use of int when as far as I can see, an unsigned int would make much more sense. One place I see this a lot is in …

Read More
Why are the fast integer types faster than the other integer types?

In ISO/IEC 9899:2018 (C18), it is stated under 7.20.1.3: 7.20.1.3 Fastest minimum-width integer types 1 Each of the following types designates an integer type that is usually fastest268) to operate with among all integer types that have at least the specified width. 2 The …

Read More
Size of character ('a') in C/C++

What is the size of character in C and C++ ? As far as I know the size of char is 1 byte in both C and C++. In C: #include <stdio.h> int main() { printf("Size of char : %d\…

Read More