错误使用sizeof操作符的一个例子是试图检查指针边界但方法错误。下例为整数数组分配内存,然后把每个元素初始化为0: int buffer[20]; int *pbuffer = buffer; for(int i=0; i<sizeof(buffer); i++) { *(pbuffer++) = 0; } C Copy 不过,sizeof(buffer)表达式返回了80,因为缓冲区长度以
理解指针和sizeof的基本概念是前提。指针在C语言中是存储内存地址的变量，其大小取决于系统架构，例如在32位系统中指针通常为4字节，64位系统中为8字节。sizeof操作符可以应用于类型或表达式，如sizeof(int)或sizeof(ptr)。如果ptr是指针变量，sizeof(ptr)计算指针的大小，而非指向的数据。例如，声明int*ptr;后，...
Size of pointer: 8 bytes Size of data pointed by pointer: 4 bytes This C program shows the size of a pointer and the size of the data it points to. It sets num = 10 and ptr as a pointer to num. sizeof(ptr) gives the size of the pointer itself, while sizeof(*ptr) gives the...
Now come to implementation of thesizeofoperator. Thesizeofin C is an operator, and all operators have been implemented at compiler level; therefore, you cannot implementsizeofoperator in standard C as a macro or function. You can do a trick to get the size of a variable by pointer arithme...
Align=Target->getPointerAlign(0);break;}break;caseType::ObjCObjectPointer:Width=Target->getPointer...
//pointer hack. #include <bits/stdc++.h> using namespace std; int main() { int arr[] = {1, 2, 3, 4, 5, 6}; int size = *(&arr + 1) - arr; cout <<"Number of elements in arr[] is " <<size; return 0; } 输出: ...
When thesizeofoperator is applied to an object of typechar, it yields 1. When thesizeofoperator is applied to an array, it yields the total number of bytes in that array, not the size of the pointer represented by the array identifier. To obtain the size of the pointer represented by ...
It should give you the size of the array right as we saw in the Sizeof operator to find array size part.But it's 8. The reason is its printing the size of the pointer and compiler generally allocated all pointers to be of 8 Bytes. So, it's not the same as printing the size of...
IN PCHARAddress, IN TYPEType, IN PCHARField ); Parameters 参数 Address Pointer to a field in an instance of a structure of type Type. 指向Type类型结构实例中某域(成员)的指针。 Type The name of the type of the structure whose base address is to be returned. For example, type IRP. ...
To initialize atype*pointer, replacesizeof(type*)in your pointer initialization expression withsizeof(type). Examples expand all Result Information Group:Programming Language:C | C++ Default:On for handwritten code, off for generated code Command-Line Syntax:PTR_SIZEOF_MISMATCH ...