Is the sizeof(some pointer) always equal to four?
For example: sizeof(char*) returns 4. As does int*, long long*, everything that I’ve tried. Are there any exceptions to this? 17 Answers 17
sizeof
How to find the ‘sizeof’ (a pointer pointing to an array)?
First off, here is some code: int main() { int days[] = {1,2,3,4,5}; int *ptr = days; printf(“%u\n”, sizeof(days)); printf(“%u\n”, sizeof(ptr)); return 0; } Is there a way to find out the size of the array that ptr is pointing to (instead of just giving its size, which is four bytes on a 32-bit system)? … Read more
How to get the size of a JavaScript object?
I want to know the size occupied by a JavaScript object. Take the following function: function Marks(){ this.maxMarks = 100; } function Student(){ this.firstName = “firstName”; this.lastName = “lastName”; this.marks = new Marks(); } Now I instantiate the student: var stud = new Student(); so that I can do stuff like stud.firstName = “new Firstname”; … Read more
Why does sizeof(x++) not increment x?
Here is the code compiled in dev c++ windows: #include <stdio.h> int main() { int x = 5; printf(“%d and “, sizeof(x++)); // note 1 printf(“%d\n”, x); // note 2 return 0; } I expect x to be 6 after executing note 1. However, the output is: 4 and 5 Can anyone explain why x … Read more
Why isn’t sizeof for a struct equal to the sum of sizeof of each member?
Why does the sizeof operator return a size larger for a structure than the total sizes of the structure’s members? 12 s 12 This is because of padding added to satisfy alignment constraints. Data structure alignment impacts both performance and correctness of programs: Mis-aligned access might be a hard error (often SIGBUS). Mis-aligned access might … Read more
How do I determine the size of an object in Python?
I want to know how to get size of objects like a string, integer, etc. in Python. Related question: How many bytes per element are there in a Python list (tuple)? I am using an XML file which contains size fields that specify the size of value. I must parse this XML and do my … Read more
