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_findfirst, _wfindfirst

Provide information about the first instance of a file name that matches the file specified in the filespec argument.

intptr_t _findfirst(
   const char *filespec,
   struct _finddata_t *fileinfo 
);
intptr_t _findfirst32(
   const char *filespec,
   struct _finddata32_t *fileinfo 
);
intptr_t _findfirst64(
   const char *filespec,
   struct _finddata64_t *fileinfo 
);
intptr_t _findfirsti64(
   const char *filespec,
   struct _finddatai64_t *fileinfo 
);
intptr_t _findfirst32i64(
   const char *filespec,
   struct _finddata32i64_t *fileinfo 
);
intptr_t _findfirst64i32(
   const char *filespec,
   struct _finddata64i32_t *fileinfo 
);
intptr_t _wfindfirst(
   const wchar_t *filespec,
   struct _wfinddata_t *fileinfo 
);
intptr_t _wfindfirst32(
   const wchar_t *filespec,
   struct _wfinddata32_t *fileinfo 
);
intptr_t _wfindfirst64(
   const wchar_t *filespec,
   struct _wfinddata64_t *fileinfo 
);
intptr_t _wfindfirsti64(
   const wchar_t *filespec,
   struct _wfinddatai64_t *fileinfo 
);
intptr_t _wfindfirst32i64(
   const wchar_t *filespec,
   struct _wfinddata32i64_t *fileinfo 
);
intptr_t _wfindfirst64i32(
   const wchar_t *filespec,
   struct _wfinddata64i32_t *fileinfo 
);

Parameters

  • filespec
    Target file specification (can include wildcard characters).

  • fileinfo
    File information buffer.

Return Value

If successful, _findfirst returns a unique search handle identifying the file or group of files that match the filespec specification, which can be used in a subsequent call to _findnext or to _findclose. Otherwise, _findfirst returns –1 and sets errno to one of the following values.

  • EINVAL
    Invalid parameter: filespec or fileinfo was NULL. Or, the operating system returned an unexpected error.

  • ENOENT
    File specification that could not be matched.

  • ENOMEM
    Insufficient memory.

  • EINVAL
    Invalid file name specification or the file name given was larger than MAX_PATH.

For more information about these and other return codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.

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 with either the _findfirst or _findnext function (or any variants). This frees resources used by these functions in your application.

The variations of these functions that have 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 numeric suffix (32 or 64) indicates the size of the time type; the second suffix is either i32 or i64, and indicates 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 i32 or i64 suffix is omitted if it is the same as the size of the time type, so _findfirst64 also supports 64-bit file lengths and _findfirst32 supports only 32-bit file lengths.

These functions use various forms of the _finddata_t structure for the fileinfo parameter. For more information about the structure, see _find, _wfind Functions.

The variations that use a 64-bit time type enable file-creation dates to be expressed up through 23:59:59, December 31, 3000, UTC. Those that use 32-bit time types represent dates only 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 _findfirst or _wfindfirst or, if you need to support file sizes larger than 3 GB, use _findfirsti64 or _wfindfirsti64. All these functions use the 64-bit time type in Visual C++ 2005. In earlier 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 revert to the old behavior. If _USE_32BIT_TIME_T is defined, _findfirst, _finfirsti64, and their corresponding Unicode versions use a 32-bit time.

Time Type and File Length Type Variations of _findfirst

Functions

_USE_32BIT_TIME_T defined?

Time type

File length type

_findfirst, _wfindfirst

Not defined

64-bit

32-bit

_findfirst, _wfindfirst

Defined

32-bit

32-bit

_findfirst32, _wfindfirst32

Not affected by the macro definition

32-bit

32-bit

_findfirst64, _wfindfirst64

Not affected by the macro definition

64-bit

64-bit

_findfirsti64, _wfindfirsti64

Not defined

64-bit

64-bit

_findfirsti64, _wfindfirsti64

Defined

32-bit

64-bit

_findfirst32i64, _wfindfirst32i64

Not affected by the macro definition

32-bit

64-bit

_findfirst64i32, _wfindfirst64i32

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

_tfindfirst

_findfirst

_findfirst

_wfindfirst

_tfindfirst32

_findfirst32

_findfirst32

_wfindfirst32

_tfindfirst64

_findfirst64

_findfirst64

_wfindfirst64

_tfindfirsti64

_findfirsti64

_findfirsti64

_wfindfirsti64

_tfindfirst32i64

_findfirst32i64

_findfirst32i64

_wfindfirst32i64

_tfindfirst64i32

_findfirst64i32

_findfirst64i32

_wfindfirst64i32

Requirements

Function

Required header

_findfirst

<io.h>

_findfirst32

<io.h>

_findfirst64

<io.h>

_findfirsti64

<io.h>

_findfirst32i64

<io.h>

_findfirst64i32

<io.h>

_wfindfirst

<io.h> or <wchar.h>

_wfindfirst32

<io.h> or <wchar.h>

_wfindfirst64

<io.h> or <wchar.h>

_wfindfirsti64

<io.h> or <wchar.h>

_wfindfirst32i64

<io.h> or <wchar.h>

_wfindfirst64i32

<io.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

System::IO::DirectoryInfo::GetFiles

See Also

Concepts

System Calls

_find, _wfind Functions