指针链 / Pointer chains 指针链经常被用来访问结构体的信息,比如,下面的这段常见的代码: typedef struct { int x, y, z; } Point3; typedef struct { Point3 *pos, *direction; } Object; void InitPos1(Object *p) { p->pos->x = 0; p->pos->y = 0; p->pos->z = 0; } 代码中,处理...
#include<stdio.h>#include<stdlib.h>typedefvoid(*FunType)(int);//前加一个typedef关键字,这样就定义一个名为FunType函数指针类型,而不是一个FunType变量。//形式同 typedef int* PINT;voidmyFun(intx);voidhisFun(intx);voidherFun(intx);voidcallFun(FunType fp,intx);intmain(){ callFun(myFun,1...
取模运算的替换 / An alternative for modulo arithmetic 我们一般使用取余运算进行取模，不过，有时候使用 if 语句来重写也是可行的。考虑下面的两个例子：uintmodulo_func1 (uint count)return(++count %60);}uintmodulo_func2 (uint count)if(++count >=60)count =0;return (count);第二个例子要比第一...
AfxGetThread() returns NULL pointer to pThread in winmain.cpp afxwin1.inl ASSERT error in AfxGetResourceHandle() already defined in .obj Alternative for strptime() AlwaysCreate -> unsuccessfulbuild ambiguous symbol An error occurred while creating or opening the C++ browsing database file... Any...
void print_data_of_a_structure ( const Thestruct *data_pointer) { ...printf contents of the structure... } 1. 2. 3. 4. 这个样例代码告知编译器在函数内部不会改变外部结构体的内容。訪问他们的时候,不须要重读。还能够确保编译器捕捉不论什么改动这个仅仅读结构体的代码,给结构体以额外的保护。
它告诉系统此报文段中有紧急数据,应尽快传送(相当于高优先级的数据), 且上图中的 Urgent Pointer 字段也会被启用。 ACK:确认比特(Acknowledge)。只有当 ACK=1 时确认号字段才有效,代表这个封包为确认封包。当 ACK=0 时,确认号无效。 PSH:(Push function)若为 1 时,代表要求对方立即传送缓冲区内的其他...
The alternative is also to just silence the warning retrieve(0, (void**)&pn);. Note that, technically, your code is invalid. You can't assign to a int * pointer using void ** handle. Consider instead returning a void * pointer and assigning the exit code by a pointer. This similarly...
printf("Value of pi: %p\n", (void*)pi); Pointers to void is explained in Pointer to void. To keep our examples simple, we will use the %p specifier and not cast the address to a pointer to void. Virtual memory and pointers To further complicate displaying addresses, the pointer addres...
Chapter9Pointer(指针)9.1Theconceptionofthepointerandpointervariable9.2Pointervariablepointstoavariable9.3Pointerpointstoanarray9.4Pointerpointstoastring9.5..
指针链 / Pointer chains 指针链经常被用来访问结构体的信息,比如,下面的这段常见的代码: typedefstruct{int x, y, z; } Point3; typedef struct{ Point3 *pos, *direction; } Object;voidInitPos1(Object *p) p->pos->x =0; p->pos->y =0; p->pos->z =0; 代码中,处理器在每次赋值操作的时...