sizeof operator — Size of type operator
unary-expr := sizeof ( type-id ) | sizeof unary-expr
At compile time, the sizeof
operator returns the amount of memory required to hold an object whose
type is type-id
or the type of
unary-expr. In the latter case,
unary-expr is not evaluated. The size of a type
includes any padding that the compiler adds to it, so the size of an
array of N
elements is always
equal to N
times the size of a
single element.
By definition, sizeof(char)
is 1
, so you can think of the size
of other types as multiples of the size of a character. The expression
type is std::size_t
.