使用 C++ 的迭代目录列表出错

我遇到了使用C++在Windows上列出目录的代码，并且我知道您可以使用以下API搜索目录：FindFirstFileEx，FindNextFile和CloseFind。您需要 #include，这将使您能够访问Windows API。

我无法理解这段代码是如何工作的，因此无法找出编译错误。

#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <strcat.h>
#pragma comment(lib, "User32.lib")
void DisplayErrorBox(LPTSTR lpszFunction);
int _tmain(int argc, TCHAR *argv[])
{
 WIN32_FIND_DATA ffd;
 LARGE_INTEGER filesize;
 TCHAR szDir[MAX_PATH];
 size_t length_of_arg;
 HANDLE hFind = INVALID_HANDLE_VALUE;
 DWORD dwError=0;
// If the directory is not specified as a command-line argument,
// print usage.
if(argc != 2)
{
   _tprintf(TEXT("nUsage: %s <directory name>n"), argv[0]);
   return (-1);
}
// Check that the input path plus 3 is not longer than MAX_PATH.
// Three characters are for the "*" plus NULL appended below.
StringCchLength(argv[1], MAX_PATH, &length_of_arg);
if (length_of_arg > (MAX_PATH - 3))
{
  _tprintf(TEXT("nDirectory path is too long.n"));
   return (-1);
}
_tprintf(TEXT("nTarget directory is %snn"), argv[1]);
// Prepare string for use with FindFile functions.  First, copy the
// string to a buffer, then append '*' to the directory name.
StringCchCopy(szDir, MAX_PATH, argv[1]);
StringCchCat(szDir, MAX_PATH, TEXT("\*"));
// Find the first file in the directory.
hFind = FindFirstFile(szDir, &ffd);
if (INVALID_HANDLE_VALUE == hFind)
{
   DisplayErrorBox(TEXT("FindFirstFile"));
   return dwError;
}
// List all the files in the directory with some info about them.
do
{
   if (ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
   {
      _tprintf(TEXT("  %s   <DIR>n"), ffd.cFileName);
   }
   else
   {
      filesize.LowPart = ffd.nFileSizeLow;
      filesize.HighPart = ffd.nFileSizeHigh;
      _tprintf(TEXT("  %s   %ld bytesn"), ffd.cFileName, filesize.QuadPart);
  }
}
while (FindNextFile(hFind, &ffd) != 0);
dwError = GetLastError();
if (dwError != ERROR_NO_MORE_FILES)
{
   DisplayErrorBox(TEXT("FindFirstFile"));
}
FindClose(hFind);
return dwError;

}

void DisplayErrorBox(LPTSTR lpszFunction)
{
    // Retrieve the system error message for the last-error code
 LPVOID lpMsgBuf;
 LPVOID lpDisplayBuf;
 DWORD dw = GetLastError();
 FormatMessage(
     FORMAT_MESSAGE_ALLOCATE_BUFFER |
     FORMAT_MESSAGE_FROM_SYSTEM |
     FORMAT_MESSAGE_IGNORE_INSERTS,
     NULL,
     dw,
     MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
     (LPTSTR) &lpMsgBuf,
     0, NULL );
 // Display the error message and clean up
 lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT,
      (lstrlen((LPCTSTR)lpMsgBuf)+lstrlen((LPCTSTR)lpszFunction)+40)*sizeof(TCHAR));
 StringCchPrintf((LPTSTR)lpDisplayBuf,
    LocalSize(lpDisplayBuf) / sizeof(TCHAR),
    TEXT("%s failed with error %d: %s"),
    lpszFunction, dw, lpMsgBuf);
MessageBox(NULL, (LPCTSTR)lpDisplayBuf, TEXT("Error"), MB_OK);
LocalFree(lpMsgBuf);
LocalFree(lpDisplayBuf);
}

在代码块上给出以下错误：

   fatal error: strcat.h: No such file or directory
   #include <strcat.h>
                ^

编译终止。