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如何在void pf下添加文件路径参数？（我是 C++ 新手）

正如您可能看到的，我正在考虑将某个文件的缓存强制到物理内存中。

代码：

#include <windows.h>
#include <cstdio>

void pf(const char* name) {

HANDLE file = CreateFile(name, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, 0,   OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
if(file == INVALID_HANDLE_VALUE) { printf("couldn't open %s\n", name); return; };

unsigned int len  = GetFileSize(file, 0);

HANDLE mapping  = CreateFileMapping(file, 0, PAGE_READONLY, 0, 0, 0);
if(mapping == 0) { printf("couldn't map %s\n", name); return; }

const char* data = (const char*) MapViewOfFile(mapping, FILE_MAP_READ, 0, 0, 0);

if(data)
{
    printf("prefetching %s... ", name);

    // need volatile or need to use result - compiler will otherwise optimize out whole loop
    volatile unsigned int touch = 0;

    for(unsigned int i = 0; i < len; i += 4096)
        touch += data[i];
}
else
    printf("couldn't create view of %s\n", name);

UnmapViewOfFile(data);
CloseHandle(mapping);
CloseHandle(file);
}

int main(int argc, const char** argv)
{
if(argc >= 2) for(int i = 1; argv[i]; ++i) pf(argv[i]);
return 0;
}
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1 回答 1

0

您的问题措辞非常糟糕，显然是因为您对 C++ 几乎一无所知。这将为您提供入门的方法。用这个替换主函数：

int main(int argc, const char** argv)
{
    pf("C:\\SomeDir\\SomeFile.ext");
    return 0;
}

然后买一本书，开始学习字符串和函数是如何工作的。

于 2013-11-08T03:27:06.770 回答