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Same code, same script, different results


Hello, I am using the latest Cygwin with all packages updated (running Windows XP Professional SP2) and I'm having a problem with a simple C++ program that uses the Win32 API to scan a directory (recursively or non-recursively, depending on user input). The code is as follows:

#include <windows.h>
#include <cstdio> /* sprintf() */
#include <cstdlib> /* EXIT_FAILURE, EXIT_SUCCESS */
#include <cstring> /* strcat(), strcmp(), strcpy(), strlen() */
#include <iostream>

using std::cerr;
using std::cout;
using std::endl;
using std::sprintf;
using std::strcat;
using std::strcmp;
using std::strcpy;
using std::strlen;

static void directory_scan(char* search_directory,
                                    bool recursive = true);

static bool ends_with_backslash(const char* const str);

static void handle_find_first_file_error(const char* const current_directory);

int
main(int argc, char* argv[])
{
if(argc < 2)
{
cerr << "You must pass the (full) starting path as an argument." << endl;


     return EXIT_FAILURE;
  }

bool recursive = true;

  if(argc >= 3)
  {
     if(strcmp(argv[2], "--non-recursive") == 0)
     {
        recursive = false;

        cout << "Will perform a non-recursive scan of directory "
             << argv[1] << "." << endl;
     }
     else
     {
        cerr << "Ignoring unknown option " << argv[2] << "." << endl;
     }
  }

  if(strlen(argv[1]) > MAX_PATH)
  {
     cerr << "Path too long! Max length is " << MAX_PATH << "." << endl;

     return EXIT_FAILURE;
  }

/* Since directory_scan() may change the string passed to it, *
* we don't pass argv[1] directly. Instead, we pass a pointer to a copy *
* of the string in argv[1]. */
char directory[MAX_PATH + 1];


strcpy(directory, argv[1]);

directory_scan(directory, recursive);

  return EXIT_SUCCESS;
}

static void
directory_scan(char* current_directory, bool recursive)
{
  if(!ends_with_backslash(current_directory))
  {
     strcat(current_directory, "\\");
  }

char find_first_file_string[MAX_PATH + 5];

sprintf(find_first_file_string, "%s*.*", current_directory);

WIN32_FIND_DATA find_data;

HANDLE file_handle = FindFirstFile(find_first_file_string, &find_data);

  if(file_handle == INVALID_HANDLE_VALUE)
  {
     handle_find_first_file_error(current_directory);

     /* We don't throw an exception here, because it might just be this  *
      * one directory we can't open (maybe protected by the OS), and we  *
      * don't want to break any recursion because of it. Besides, if we  *
      * throw an exception here all previously opened file handles *
      * will not be closed.                                              */
     return;
  }

  do
  {
     if(strcmp(find_data.cFileName, ".") != 0 &&
        strcmp(find_data.cFileName, "..") != 0)
     {
        char complete_file_name[MAX_PATH + 1];

        sprintf(complete_file_name,
                "%s%s",
                current_directory,
                find_data.cFileName);

cout << complete_file_name << endl;

        if(find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY &&
           recursive)
        {
           directory_scan(complete_file_name, recursive);
        }
     }
  }while(FindNextFile(file_handle, &find_data));

  FindClose(file_handle);
}

static bool
ends_with_backslash(const char* const str)
{
  return (str[strlen(str) - 1] == '\\');
}

static void
handle_find_first_file_error(const char* const current_directory)
{
  unsigned long error = GetLastError();

char message[128];

  FormatMessage(
     FORMAT_MESSAGE_FROM_SYSTEM,
     NULL,
     error,
     MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
     message,
     sizeof(message),
     NULL
     );

   cerr << "FindFirstFile() returned INVALID_HANDLE_VALUE." << endl;
   cerr << "Current directory was " << current_directory << "." << endl;
   cerr << "error code was: " << message << endl;
}

If I test this program with the following bash script:
#!/bin/bash
echo "Performing a scan without using recursion"
./directory_scanner.exe c:\\coding\\cygwin\\c++\\ --non-recursive

the output is:
Performing a scan without using recursion
Ignoring unknown option --non-recursive.
[Recursive listing snipped]

If I compile the exactly the same code under MSVC++ 7.1 and invoke the executable it produces with the exactly the same script, the output is:
Performing a scan without using recursion
Will perform a non-recursive scan of directory c:\coding\cygwin\c++\.
[Non-recursive listing snipped]


What's going on here? Why doesn't strcmp() return 0 if compiled with g++ with the input given above?

/ Mikael



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