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_stat, _stat32, _stat64, _stati64, _stat32i64, _stat64i32, _wstat, _wstat32, _wstat64, _wstati64, _wstat32i64, _wstat64i32

  • Άρθρο

Get status information on a file.

Syntax

int _stat(
   const char *path,
   struct _stat *buffer
);
int _stat32(
   const char *path,
   struct __stat32 *buffer
);
int _stat64(
   const char *path,
   struct __stat64 *buffer
);
int _stati64(
   const char *path,
   struct _stati64 *buffer
);
int _stat32i64(
   const char *path,
   struct _stat32i64 *buffer
);
int _stat64i32(
   const char *path,
   struct _stat64i32 *buffer
);
int _wstat(
   const wchar_t *path,
   struct _stat *buffer
);
int _wstat32(
   const wchar_t *path,
   struct __stat32 *buffer
);
int _wstat64(
   const wchar_t *path,
   struct __stat64 *buffer
);
int _wstati64(
   const wchar_t *path,
   struct _stati64 *buffer
);
int _wstat32i64(
   const wchar_t *path,
   struct _stat32i64 *buffer
);
int _wstat64i32(
   const wchar_t *path,
   struct _stat64i32 *buffer
);

Parameters

path
Pointer to a string containing the path of existing file or directory.

buffer
Pointer to structure that stores results.

Return value

Each of these functions returns 0 if the file-status information is obtained. A return value of -1 indicates an error, in which case errno is set to ENOENT, indicating that the filename or path couldn't be found. A return value of EINVAL indicates an invalid parameter; errno is also set to EINVAL in this case.

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

The date stamp on a file can be represented if it's later than midnight, January 1, 1970, and before 23:59:59, December 31, 3000, UTC, unless you use _stat32 or _wstat32, or have defined _USE_32BIT_TIME_T, in which case the date can be represented only until 23:59:59 January 18, 2038, UTC.

Remarks

The _stat function obtains information about the file or directory specified by path and stores it in the structure pointed to by buffer. _stat automatically handles multibyte-character string arguments as appropriate, recognizing multibyte-character sequences according to the multibyte code page currently in use.

_wstat is a wide-character version of _stat; the path argument to _wstat is a wide-character string. _wstat and _stat behave identically except that _wstat doesn't handle multibyte-character strings.

Variations of these functions support 32-bit or 64-bit time types, and 32-bit or 64-bit file lengths. 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.

_stat is equivalent to _stat64i32, and struct _stat contains a 64-bit time, unless _USE_32BIT_TIME_T is defined, in which case the old behavior is in effect; _stat uses a 32-bit time, and struct _stat contains a 32-bit time. The same is true for _stati64.

Note

_wstat does not work with Windows Vista symbolic links. In these cases, _wstat will always report a file size of 0. _stat does work correctly with symbolic links. The _stat family of functions use CreateFile in Visual Studio 2015, instead of FindFirstFile as in Visual Studio 2013 and earlier. This means that _stat on a path ending with a slash succeeds if the path refers to a directory, as opposed to before when the function would error with errno set to ENOENT.

This function validates its parameters. If either path or buffer is NULL, the invalid parameter handler is invoked, as described in Parameter validation.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Time type and file length type variations of _stat

Functions _USE_32BIT_TIME_T defined Time type File length type
_stat, _wstat Not defined 64-bit 32-bit
_stat, _wstat Defined 32-bit 32-bit
_stat32, _wstat32 Not affected by the macro definition 32-bit 32-bit
_stat64, _wstat64 Not affected by the macro definition 64-bit 64-bit
_stati64, _wstati64 Not defined 64-bit 64-bit
_stati64, _wstati64 Defined 32-bit 64-bit
_stat32i64, _wstat32i64 Not affected by the macro definition 32-bit 64-bit
_stat64i32, _wstat64i32 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
_tstat _stat _stat _wstat
_tstat64 _stat64 _stat64 _wstat64
_tstati64 _stati64 _stati64 _wstati64
_tstat32i64 _stat32i64 _stat32i64 _wstat32i64
_tstat64i32 _stat64i32 _stat64i32 _wstat64i32

The _stat structure, defined in SYS\STAT.H, includes the following fields.

Field Description
st_gid Numeric identifier of group that owns the file (UNIX-specific) This field will always be zero on Windows systems. A redirected file is classified as a Windows file.
st_atime Time of last access of file. Valid on NTFS but not on FAT formatted disk drives.
st_ctime Time of creation of file. Valid on NTFS but not on FAT formatted disk drives.
st_dev Drive number of the disk containing the file (same as st_rdev).
st_ino Number of the information node (the inode) for the file (UNIX-specific). On UNIX file systems, the inode describes the file date and time stamps, permissions, and content. When files are hard-linked to one another, they share the same inode. The inode, and therefore st_ino, has no meaning in the FAT, HPFS, or NTFS file systems.
st_mode Bit mask for file-mode information. The _S_IFDIR bit is set if path specifies a directory; the _S_IFREG bit is set if path specifies an ordinary file or a device. User read/write bits are set according to the file's permission mode; user execute bits are set according to the filename extension.
st_mtime Time of last modification of file.
st_nlink Always 1 on non-NTFS file systems.
st_rdev Drive number of the disk containing the file (same as st_dev).
st_size Size of the file in bytes; a 64-bit integer for variations with the i64 suffix.
st_uid Numeric identifier of user who owns file (UNIX-specific). This field will always be zero on Windows systems. A redirected file is classified as a Windows file.

If path refers to a device, the st_size, various time fields, st_dev, and st_rdev fields in the _stat structure are meaningless. Because STAT.H uses the _dev_t type that is defined in TYPES.H, you must include TYPES.H before STAT.H in your code.

Requirements

Routine Required header Optional headers
_stat, _stat32, _stat64, _stati64, _stat32i64, _stat64i32 <sys/types.h> followed by <sys/stat.h> <errno.h>
_wstat, _wstat32, _wstat64, _wstati64, _wstat32i64, _wstat64i32 <sys/types.h> followed by <sys/stat.h> or <wchar.h> <errno.h>

For more compatibility information, see Compatibility.

Example

// crt_stat.c
// This program uses the _stat function to
// report information about the file named crt_stat.c.

#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <errno.h>

int main( void )
{
   struct _stat buf;
   int result;
   char timebuf[26];
   char* filename = "crt_stat.c";
   errno_t err;

   // Get data associated with "crt_stat.c":
   result = _stat( filename, &buf );

   // Check if statistics are valid:
   if( result != 0 )
   {
      perror( "Problem getting information" );
      switch (errno)
      {
         case ENOENT:
           printf("File %s not found.\n", filename);
           break;
         case EINVAL:
           printf("Invalid parameter to _stat.\n");
           break;
         default:
           /* Should never be reached. */
           printf("Unexpected error in _stat.\n");
      }
   }
   else
   {
      // Output some of the statistics:
      printf( "File size     : %ld\n", buf.st_size );
      printf( "Drive         : %c:\n", buf.st_dev + 'A' );
      err = ctime_s(timebuf, 26, &buf.st_mtime);
      if (err)
      {
         printf("Invalid arguments to ctime_s.");
         exit(1);
      }
      printf( "Time modified : %s", timebuf );
   }
}

File size     : 732
Drive         : C:
Time modified : Thu Feb 07 14:39:36 2002

See also

File handling
_access, _waccess
_fstat, _fstat32, _fstat64, _fstati64, _fstat32i64, _fstat64i32
_getmbcp
_setmbcp