vs2005下的dirent.h

dirent.h是gcc下的一个头文件，而在VS2005中是没有的。这个文件中封装了几个对目录进行操作函数：

static DIR *opendir (const char *dirname);static struct dirent *readdir (DIR *dirp);static int closedir (DIR *dirp);

 对于在linux->windows之间进行程序移植来讲常常会造成一些困扰，在网上仔细搜了一下，发现原来已经有位好同志写了相应的移植代码，如下所示：

typedef struct dirent {  /* name of current directory entry (a multi-byte character string) */  char d_name[MAX_PATH + 1];

  /* file attributes */  WIN32_FIND_DATA data;} dirent;

typedef struct DIR {  /* current directory entry */  dirent current;

  /* is there an un-processed entry in current? */  int cached;

  /* file search handle */  HANDLE search_handle;

  /* search pattern (3 = zero terminator + pattern "//*") */  TCHAR patt[MAX_PATH + 3];} DIR;

static DIR *opendir (const char *dirname);static struct dirent *readdir (DIR *dirp);static int closedir (DIR *dirp);

/* use the new safe string functions introduced in Visual Studio 2005 */#if defined(_MSC_VER) && _MSC_VER >= 1400# define STRNCPY(dest,src,size) strncpy_s((dest),(size),(src),_TRUNCATE)#else# define STRNCPY(dest,src,size) strncpy((dest),(src),(size))#endif

/* * Open directory stream DIRNAME for read and return a pointer to the * internal working area that is used to retrieve individual directory * entries. */static DIR*opendir(    const char *dirname){  DIR *dirp;  assert (dirname != NULL);  assert (strlen (dirname) < MAX_PATH);

  /* construct new DIR structure */  dirp = (DIR*) malloc (sizeof (struct DIR));  if (dirp != NULL) {    TCHAR *p;        /* prepare search pattern */#ifdef _UNICODE

    /* convert directory name to wide character string */    MultiByteToWideChar(        CP_ACP,                                /* code page */        0,                                     /* conversion flags */        dirname,                               /* mb-string to convert */        -1,                                    /* length of mb-string */        dirp->patt,                            /* wc-string to produce */        MAX_PATH);                             /* max length of wc-string */    dirp->patt[MAX_PATH] = '/0';        /* append search pattern to directory name */    p = wcschr (dirp->patt, '/0');    if (dirp->patt < p  &&  *(p-1) != '//'  &&  *(p-1) != ':') {      *p++ = '//';    }    *p++ = '*';    *p = '/0';

#else /* !_UNICODE */        /* take directory name... */    STRNCPY (dirp->patt, dirname, sizeof(dirp->patt));    dirp->patt[MAX_PATH] = '/0';        /* ... and append search pattern to it */    p = strchr (dirp->patt, '/0');    if (dirp->patt < p  &&  *(p-1) != '//'  &&  *(p-1) != ':') {      *p++ = '//';    }    *p++ = '*';    *p = '/0';    #endif /* !_UNICODE */

    /* open stream and retrieve first file */    dirp->search_handle = FindFirstFile (dirp->patt, &dirp->current.data);    if (dirp->search_handle == INVALID_HANDLE_VALUE) {      /* invalid search pattern? */      free (dirp);      return NULL;    }

    /* there is an un-processed directory entry in memory now */    dirp->cached = 1;      }  return dirp;}

  /* * Read a directory entry, and return a pointer to a dirent structure * containing the name of the entry in d_name field.  Individual directory * entries returned by this very function include regular files, * sub-directories, pseudo-directories "." and "..", but also volume labels, * hidden files and system files may be returned.   */static struct dirent *readdir(    DIR *dirp){  assert (dirp != NULL);

  if (dirp->search_handle == INVALID_HANDLE_VALUE) {    /* directory stream was opened/rewound incorrectly or it ended normally */    return NULL;  }

  /* get next directory entry */  if (dirp->cached != 0) {    /* a valid directory entry already in memory */    dirp->cached = 0;  } else {    /* read next directory entry from disk */    if (FindNextFile (dirp->search_handle, &dirp->current.data) == FALSE) {      /* the very last file has been processed or an error occured */      FindClose (dirp->search_handle);      dirp->search_handle = INVALID_HANDLE_VALUE;      return NULL;    }  }

  /* copy directory entry to d_name */#ifdef _UNICODE    /* convert entry name to multibyte */  WideCharToMultiByte(      CP_ACP,                                  /* code page */      0,                                       /* conversion flags */      dirp->current.data.cFileName,            /* wc-string to convert */      -1,                                      /* length of wc-string */      dirp->current.d_name,                    /* mb-string to produce */      MAX_PATH,                                /* max length of mb-string */      NULL,                                    /* use sys default character */      NULL);                                   /* don't care  */  dirp->current.d_name[MAX_PATH] = '/0';  #else /* !_UNICODE */

  /* copy as a multibyte character string */  STRNCPY (dirp->current.d_name, dirp->current.data.cFileName, sizeof(dirp->current.d_name));  dirp->current.d_name[MAX_PATH] = '/0';

#endif /* !_UNICODE */    return &dirp->current;}

/* * Close directory stream opened by opendir() function.  Close of the * directory stream invalidates the DIR structure as well as any previously * read directory entry. */static intclosedir(    DIR *dirp){  assert (dirp != NULL);   /* release search handle */  if (dirp->search_handle != INVALID_HANDLE_VALUE) {    FindClose (dirp->search_handle);    dirp->search_handle = INVALID_HANDLE_VALUE;  }

  /* release directory handle */  free (dirp);  return 0;}

此文件可从http://www.softagalleria.net/dirent/index.en.html下载得到，直接将它放在VS2005的include目录就OK 了！