*《精通Windows API》 5.4.2 分配和釋放可讀可寫的虛擬記憶體頁面

/* *************************************《精通Windows API》 * 範例程式碼* virtual.c* 5.4.2  分配和釋放可讀可寫的虛擬記憶體頁面**************************************//* 標頭檔　*/#include <windows.h>#include <stdio.h>/************************************** int main(void)* 功能示範虛擬記憶體的使用** 參數未使用**************************************/int main(void){SIZE_T sizeVirtual = 4000;//大小LPVOID lpRound = (LPVOID)0x100000FF;//地址MEMORY_BASIC_INFORMATION  mbi;//記憶體資訊//分配記憶體，直接分配已提交的記憶體LPVOID lpAddress = VirtualAlloc(lpRound,sizeVirtual,MEM_COMMIT|MEM_RESERVE,PAGE_READWRITE);if(lpAddress == NULL){printf("VirtualAlloc error: %d\n",GetLastError());return 1;}printf("Alloc:MEM_COMMIT|MEM_RESERVE\n");//複製資料到記憶體中CopyMemory(lpAddress,"hello",lstrlen("hello"));printf("分配、複製成功，地址：0x%.8x，內容：%s\n",lpAddress,lpAddress);//擷取記憶體資訊並列印VirtualQuery(lpAddress,&mbi,sizeof(mbi));printf("使用VirtualQuery獲得的資訊：\n""BaseAddress:0x%.8x\tAllocationBase:0x%.8x\t""AllocationProtect:0x%.8x\tRegionSize:%u\t""State:0x%.8x\tProtect:0x%.8x\tType:0x%.8x\n",mbi.BaseAddress,mbi.AllocationBase,mbi.AllocationProtect,mbi.RegionSize,mbi.State,mbi.Protect,mbi.Type);////設定為READ-ONLY屬性//if(!VirtualProtect(lpAddress,0,PAGE_READONLY,NULL))//{//printf("VirtualProtect error: %d",GetLastError());//return 1;//}////測試READ-ONLY屬性,異常//CopyMemory(lpAddress,"read only",lstrlen("read only"));//printf(lpAddress);////擷取記憶體資訊並列印//VirtualQuery(lpAddress,&mbi,sizeof(mbi));//printf("使用VirtualQuery獲得的資訊：\n"//"BaseAddress:0x%.8x\tAllocationBase:0x%.8x\t"//"AllocationProtect:0x%.8x\tRegionSize:%d\t"//"State:0x%.8x\tProtect:0x%.8x\tType:0x%.8x\n",//mbi.BaseAddress,mbi.AllocationBase,//mbi.AllocationProtect,mbi.RegionSize,//mbi.State,mbi.Protect,mbi.Type//);//DECOMMIT釋放，頁面將變為保留狀態printf("Free: DECOMMIT\n");if(!VirtualFree(lpRound,sizeVirtual,MEM_DECOMMIT)){printf("VirtualFree error: %d",GetLastError());return 1;}//擷取記憶體資訊並列印VirtualQuery(lpAddress,&mbi,sizeof(mbi));printf("使用VirtualQuery獲得的資訊：\n""BaseAddress:0x%.8x\tAllocationBase:0x%.8x\t""AllocationProtect:0x%.8x\tRegionSize:%u\t""State:0x%.8x\tProtect:0x%.8x\tType:0x%.8x\n",mbi.BaseAddress,mbi.AllocationBase,mbi.AllocationProtect,mbi.RegionSize,mbi.State,mbi.Protect,mbi.Type);//釋放記憶體printf("Free:RELEASE\n");if(!VirtualFree(lpAddress,0,MEM_RELEASE)){printf("VirtualFree error: %d",GetLastError());return 1;}return 0;}