_cscanf, _cscanf_l, _cwscanf, _cwscanf_l

Article
04/22/2008

Reads formatted data from the console. More secure versions of these functions are available; see _cscanf_s, _cscanf_s_l, _cwscanf_s, _cwscanf_s_l.

int _cscanf( 
   const char *format [,
      argument] ... 
);
int _cscanf_l( 
   const char *format,
   locale_t locale [,
      argument] ... 
);
int _cwscanf( 
   const wchar_t *format [,
      argument] ... 
);
int _cwscanf_l( 
   const wchar_t *format,
   locale_t locale [,
      argument] ... 
);

Parameters

format
Format-control string.
argument
Optional parameters.
locale
The locale to use.

Return Value

The number of fields that were successfully converted and assigned. The return value does not include fields that were read but not assigned. The return value is EOF for an attempt to read at end of file. This can occur when keyboard input is redirected at the operating-system command-line level. A return value of 0 means that no fields were assigned.

Remarks

The _cscanf function reads data directly from the console into the locations given by argument. The _getche function is used to read characters. Each optional parameter must be a pointer to a variable with a type that corresponds to a type specifier in format. The format controls the interpretation of the input fields and has the same form and function as the format parameter for the scanf function. While _cscanf normally echoes the input character, it does not do so if the last call was to _ungetch.

This function validates its parameters. If format is NULL, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, errno is set to EINVAL and the function returns EOF.

The versions of these functions with the _l suffix are identical except that they use the locale parameter passed in instead of the current thread locale.

Generic-Text Routine Mappings

TCHAR.H routine	_UNICODE and _MBCS not defined	_MBCS defined	_UNICODE defined
_tcscanf	_cscanf	_cscanf	_cwscanf
_tcscanf_l	_cscanf_l	_cscanf_l	_cwscanf_l

Requirements

Routine	Required header
_cscanf, _cscanf_l	<conio.h>
_cwscanf, _cwscanf_l	<conio.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

Example

// crt_cscanf.c
// compile with: /c /W3
/* This program prompts for a string
 * and uses _cscanf to read in the response.
 * Then _cscanf returns the number of items
 * matched, and the program displays that number.
 */

#include <stdio.h>
#include <conio.h>

int main( void )
{
   int   result, i[3];

   _cprintf_s( "Enter three integers: ");
   result = _cscanf( "%i %i %i", &i[0], &i[1], &i[2] ); // C4996
   // Note: _cscanf is deprecated; consider using _cscanf_s instead
   _cprintf_s( "\r\nYou entered " );
   while( result-- )
      _cprintf_s( "%i ", i[result] );
   _cprintf_s( "\r\n" );
}

Input

1 2 3

Output

Enter three integers: 1 2 3
You entered 3 2 1

Partager via