memory-address

问题 alist += [4] and alist = alist + [4] are different as the first changes the reference of alist whereas the latter doesn't. I tried this below on IDLE by using id() and it seems like it is correct claim. Code executed on IDLE (Python 3.6.1) >>> alist = [1, 2, 3] >>> id(alist) 50683952 >>> alist += [4] >>> id(alist) 50683952 >>> alist = alist + [4] >>> id(alist) 50533080 Here is documentation for id() : https://docs.python.org/3/library/functions.html#id Is it possible to get reference to

问题 Is there a way to get the "address" of an object? This is for demonstration purposes, I know this is a bad idea in general and if it works at all then as unsafe code. The project is tuned to allow unsafe code. However my tries were unsuccessful. The code I have so far is not compiling: unsafe static String AddressOf(Object o) { void* p = &o; return String.Format("{0}", new IntPtr(p)); } Error: Cannot take the address of, get the size of, or declare a pointer to a managed type ('object') Even

问题 class Bar: pass class Foo: def __str__(self): return "Foo instance" >> aBar = Bar() >> print aBar <__main__.Bar instance at 0x100572a28> >> aFoo = Foo() >> print aFoo Foo instance is there a way to print out the address of aFoo after overriding the str method? using >>repr(aFoo) solved my problem 回答1: At least in cpython, id provides the address. But the output is in decimal; you have to convert that to hex: >>> f = (x for x in [1,2,3]) >>> print f <generator object <genexpr> at 0x1004d22d0>

问题 In the following code, I get a different address every time for the first element of std::vector v . Why is it so? #include <memory> #include <iostream> #include <vector> int main() { std::vector<int> v; for (int i=0; i<10; ++i) { int b = i; v.push_back(b); std::cout << std::addressof(v[0]) << std::endl; } return 0; } Output: 0x603010 0x603030 0x603010 0x603010 0x603050 0x603050 0x603050 0x603050 0x603080 0x603080 回答1: Because new memory may have to be allocated for the data contained in the

问题 Recently I've time off of school for a few days and wanted to do a small program(s) experiment in C++ dealing with memory address. I wanted to see is that if a currently running program (Let call it Program A) that created a pointer to an int object in the heap, can be seen by another program and be modified (Program B). So for Program A, this is my basic code: // Program A #include <iostream> using namespace std; int main() { // Pointer to an int object in the heap int *pint = new int(15); /

问题 int a; printf("address is %u", &a); Which address is this..? I mean is this a compiler generated address i.e. virtual address or the loader given physical address in the RAM..? As it prints different address every time, I guess it must be address in the RAM. Just want to make sure. Please provide any links which give reference to your answer. 回答1: The correct answer is: "it depends." (The printf should use the "%p" directive, and cast the address to "void *", for the sake of well-defined-ness

问题 Take the following example: typedef struct array_struct { unsigned char* pointer; size_t length; } array; typedef struct vector_struct { unsigned char* pointer; // Reserved is the amount of allocated memory not being used. // MemoryLength = length + reserved; size_t length, reserved; } vector; // Example Usage: vector* vct = (vector*) calloc(sizeof(vector), 1); vct->reserved = 0; vct->length = 24; vct->pointer = (unsigned char*) calloc(arr->length, 1); array* arr = (array*) vct; printf("%i",

问题 I am studying the concept of Memory Management Unit(MMU) from the book titled "Operating System Concepts" - by Abraham Silberschatz and Galvin. Though things were fine till chapter 8. As soon I started with chapter 9, things started messing up. I am not clear about what my virtual memory is? Also, physical and logical addresses seems to be confusing now? Does it(virtual memory) exists in real or not? As per my understanding of now, the RAM of my system is what I call Physical(or main) Memory.

问题 I want to traverse a tree at GPU with OpenCL , so i assemble the tree in a contiguous block at host and i change the addresses of all pointers so as to be consistent at device as follows: TreeAddressDevice = (size_t)BaseAddressDevice + ((size_t)TreeAddressHost - (size_t)BaseAddressHost); I want the base address of the memory buffer : At host i allocate memory for the buffer, as follows: cl_mem tree_d = clCreateBuffer(...); The problem is that cl_mems are objects that track an internal

问题 (Sorry for my bad English ) How to read a value address from pointer in C#? Example: I know my pointer but the value change at application starting. 1) Start (Pointer) 0x0018F36C = ( Value) 0x0342AD68 2) Restart (Pointer) 0x0018F36C = ( Value Changed ) 0x0342AE20 Actually i have a base address 0x0018F36C but need to read value from pointer and save in long example: long addr_base = 0x0018F36C; long address; //Obviously I do not know the Address now i need to read long value from addr_base and