FindFirstFileW wildcard match - c++

Question

Consider a standalone example wherein I query for all the names in the directory with a wild card:
#include <Windows.h>
#include <fstream>
void add_file(const std::string &path)
{
std::ofstream ofs(path,std::ofstream::out);
ofs.close();
}
void foo(const std::wstring& szDir)
{
std::cout << "f1 : FindFirstFileW\n";
WIN32_FIND_DATAW ffd;
HANDLE hFind = INVALID_HANDLE_VALUE;
hFind = FindFirstFileW(szDir.c_str(), &ffd);
if (INVALID_HANDLE_VALUE == hFind)
{
std::cout << "Error in FindFirstFileW : " << GetLastError() << std::endl;
return;
}
// List all the files in the directory with some info about them.
do
{
std::wcout <<"Long file name " << " " << ffd.cFileName << std::endl;
std::wcout <<"Short file name " << " " << ffd.cAlternateFileName << std::endl;
}
while (FindNextFileW(hFind, &ffd) != 0);
FindClose(hFind);
}
int main()
{
const char odd_filename[] = {static_cast<char>(0xC4U), '.', 't', 'x', 't', 0};
add_file("C:\\mydir1\\777.Txt");
add_file(std::string("C:\\mydir1\\") + std::string(odd_filename));
foo(L"C:\\mydir1\\7*");
return 0;
}
This gives me output as below
f1 : FindFirstFileW
Long file name 777.Txt
Short file name
Long file name ─.txt
Short file name 7F7E~1.TXT
Why does FindFirstFileW give back the second file name Ä.txt as a match ?

Answer 1

The wildcard match is applied to both long and short file names. The second file has a short name of 7F7E~1.TXT and so matches 7*.
The documentation covers this like so:
The following list identifies some other search characteristics:
The search is performed strictly on the name of the file, not on any attributes such as a date or a file type (for other options, see
FindFirstFileEx).
The search includes the long and short file names.
An attempt to open a search with a trailing backslash always fails.
Passing an invalid string, NULL, or empty string for the lpFileName parameter is not a valid use of this function. Results in this case
are undefined.
The second bullet point is the pertinent one.