_findnext, _wfindnext

Artigo
07/22/2011

Find the next name, if any, that matches the filespec argument in a previous call to _findfirst, and then alter the fileinfo structure contents accordingly.

int _findnext(
   intptr_t handle,
   struct _finddata_t *fileinfo 
);
int _findnext32(
   intptr_t handle,
   struct _finddata32_t *fileinfo 
);
int _findnext64(
   intptr_t handle,
   struct __finddata64_t *fileinfo 
);
int _findnexti64(
   intptr_t handle,
   struct __finddatai64_t *fileinfo 
);
int _findnext32i64(
   intptr_t handle,
   struct _finddata32i64_t *fileinfo 
);
int _findnext64i32(
   intptr_t handle,
   struct _finddata64i32_t *fileinfo 
);
int _wfindnext(
   intptr_t handle,
   struct _wfinddata_t *fileinfo 
);
int _wfindnext32(
   intptr_t handle,
   struct _wfinddata32_t *fileinfo 
);
int _wfindnext64(
   intptr_t handle,
   struct _wfinddata64_t *fileinfo 
);
int _wfindnexti64(
   intptr_t handle,
   struct _wfinddatai64_t *fileinfo 
);
int _wfindnext32i64(
   intptr_t handle,
   struct _wfinddatai64_t *fileinfo 
);
int _wfindnext64i32(
   intptr_t handle,
   struct _wfinddata64i32_t *fileinfo 
);

Parameters

handle
Search handle returned by a previous call to _findfirst.
fileinfo
File information buffer.

Return Value

If successful, returns 0. Otherwise, returns –1 and sets errno to a value indicating the nature of the failure. Possible error codes are shown in the following table.

EINVAL
Invalid parameter: fileinfo was NULL. Or, the operating system returned an unexpected error.
ENOENT
No more matching files could be found.
ENOMEM
Not enough memory or the file name's length exceeded MAX_PATH.

If an invalid parameter is passed in, these functions invoke the invalid parameter handler, as described in Parameter Validation.

Remarks

You must call _findclose after you are finished using either the _findfirst or _findnext function (or any variants). This frees up resources used by these functions in your application.

The variations of these functions with the w prefix are wide-character versions; otherwise, they are identical to the corresponding single-byte functions.

Variations of these functions support 32-bit or 64-bit time types and 32-bit or 64-bit file sizes. The first numerical suffix (32 or 64) indicates the size of the time type used; the second suffix is either i32 or i64, indicating whether the file size is represented as a 32-bit or 64-bit integer. For information about which versions support 32-bit and 64-bit time types and file sizes, see the following table. The variations that use a 64-bit time type allow file-creation dates to be expressed up through 23:59:59, December 31, 3000, UTC; whereas those using 32-bit time types only represent dates through 19:14:07 January 18, 2038, UTC. Midnight, January 1, 1970, is the lower bound of the date range for all these functions.

Unless you have a specific reason to use the versions that specify the time size explicitly, use _findnext or _wfindnext or, if you need to support file sizes greater than 3 GB, use _findnexti64 or _wfindnexti64. All these functions use the 64-bit time type. In previous versions, these functions used a 32-bit time type. If this is a breaking change for an application, you might define _USE_32BIT_TIME_T to get the old behavior. If _USE_32BIT_TIME_T is defined, _findnext, _finnexti64 and their corresponding Unicode versions use a 32-bit time.

Time Type and File Length Type Variations of _findnext

Functions	_USE_32BIT_TIME_T defined?	Time type	File length type
_findnext, _wfindnext	Not defined	64-bit	32-bit
_findnext, _wfindnext	Defined	32-bit	32-bit
_findnext32, _wfindnext32	Not affected by the macro definition	32-bit	32-bit
_findnext64, _wfindnext64	Not affected by the macro definition	64-bit	64-bit
_findnexti64, _wfindnexti64	Not defined	64-bit	64-bit
_findnexti64, _wfindnexti64	Defined	32-bit	64-bit
_findnext32i64, _wfindnext32i64	Not affected by the macro definition	32-bit	64-bit
_findnext64i32, _wfindnext64i32	Not affected by the macro definition	64-bit	32-bit

Generic-Text Routine Mappings

Tchar.h routine	_UNICODE and _MBCS not defined	_MBCS defined	_UNICODE defined
_tfindnext	_findnext	_findnext	_wfindnext
_tfindnext32	_findnext32	_findnext32	_wfindnext32
_tfindnext64	_findnext64	_findnext64	_wfindnext64
_tfindnexti64	_findnexti64	_findnexti64	_wfindnexti64
_tfindnext32i64	_findnext32i64	_findnext32i64	_wfindnext32i64
_tfindnext64i32	_findnext64i32	_findnext64i32	_wfindnext64i32

Requirements

Function	Required header
_findnext	<io.h>
_findnext32	<io.h>
_findnext64	<io.h>
_findnexti64	<io.h>
_findnext32i64	<io.h>
_findnext64i32	<io.h>
_wfindnext	<io.h> or <wchar.h>
_wfindnext32	<io.h> or <wchar.h>
_wfindnext64	<io.h> or <wchar.h>
_wfindnexti64	<io.h> or <wchar.h>
_wfindnext32i64	<io.h> or <wchar.h>
_wfindnext64i32	<io.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

.NET Framework Equivalent

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

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