How to copy multiple files with CopyFile function?

Question

Here is an example my code to copy file from src to dst:

int main() {

    const wchar_t* file[3] = { L"\\abc.txt", L"\\def.txt", L"\\ghi.txt" };

    for (int i = 0; i < 3; i++) {
        wchar_t* src = funcA();
        wchar_t* dst = funcB();
        wcscat(dst, file[i]);
        wcscat(src, file[i]);
        CopyFileW(src, dst, TRUE);
    }
}

Is there a better way to do that? Can I optimize the code by not running the funcA and funcB many times?

Answer 1

After you fix the errors, your code is copying the file to itself. It boils down to this:

const wchar_t* file[3] = { L"\\abc.txt", L"\\def.txt", L"\\ghi.txt" };
for(int i = 0; i < _countof(file); i++)
    CopyFile(file[i], file[i], TRUE);

It's just copying "\\abc.txt" to "\\abc.txt", and "\\def.txt" to "\\def.txt", etc.

Presumably your intention is to copy multiple files from one directory to another directory. For example copy "abc.txt" to "c:\\target\\abc.txt", etc.

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

int main(void)
{
    const wchar_t* files[3] = { L"1.txt", L"2.txt", L"3.txt" };

    wchar_t *directory = L"c:\\target";
    wchar_t dst[MAX_PATH] = { 0 };
    for(int i = 0; i < _countof(files); i++)
    {
        swprintf(dst, _countof(dst), L"%ls\\%ls", directory, files[i]);
        CopyFileW(files[i], dst, TRUE);
    }

    return 0;
}

Note that I changed the source to "abc.txt" and changed the format specifier in swprintf

In a practical application you may want to copy "c:\\src\\1.txt" to "c:\\dst\\1.txt", like this code:

#define UNICODE
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <Shlwapi.h>

#pragma comment(lib, "Shlwapi.lib")//Add library (Visual Studio specific)

int main(void)
{
    const wchar_t* files[3] =
        { L"c:\\src\\1.txt", L"c:\\src\\2.txt", L"c:\\src\\3.txt" };

    wchar_t *directory = L"c:\\dst";
    wchar_t dst[MAX_PATH] = { 0 };

    if(!PathFileExists(directory))
    {
        wprintf(L"path error\n");
        return 0;
    }

    for(int i = 0; i < _countof(files); i++)
    {
        swprintf(dst, _countof(dst), L"%ls\\%ls", directory, PathFindFileName(files[i]));
        //CopyFile(files[i], dst, TRUE);
        wprintf(L"copy %s to %s\n", files[i], dst);
    }

    return 0;
}