What is size_t in C++?
size_t is a base unsigned integer type of C/C++ language. It is the type of the result returned by sizeof operator. The type’s size is chosen so that it can store the maximum size of a theoretically possible array of any type. size_t type is usually used for loop counters, array indexing, and address arithmetic.
Why Use size_t?
Using size_t appropriately makes your source code a little more self-documenting. When you see an object declared as a size_t, you immediately know it represents a size in bytes or an index, rather than an error code or a general arithmetic value.
size_t Data Type in Linux
Data Type: size_t
This is an unsigned integer type used to represent the sizes of objects. The result of the sizeof operator is of this type, and functions such as malloc and memcpy accept arguments of this type to specify object sizes.
Comparison with int
When writing C code you should always use size_t whenever dealing with memory ranges. The int type, on the other hand, is basically defined as the size of the (signed) integer value that the host machine can use to most efficiently perform integer arithmetic.
size_t in Arduino
size_t is a data type capable of representing the size of any object in bytes. Examples of the use of size_t are the return type of sizeof() and Serial.