_snscanf, _snscanf_l, _snwscanf, _snwscanf_l
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Reads formatted data of a specified length from a string. More secure versions of these functions are available; see _snscanf_s, _snscanf_s_l, _snwscanf_s, _snwscanf_s_l.
Syntax
int __cdecl _snscanf(
const char * input,
size_t length,
const char * format,
...
);
int __cdecl _snscanf_l(
const char * input,
size_t length,
const char * format,
locale_t locale,
...
);
int __cdecl _snwscanf(
const wchar_t * input,
size_t length,
const wchar_t * format,
...
);
int __cdecl _snwscanf_l(
const wchar_t * input,
size_t length,
const wchar_t * format,
locale_t locale,
...
);
Parameters
input
Input string to examine.
length
Number of characters to examine in input.
format
One or more format specifiers.
... (optional)
Variables that will be used to store the values extracted from the input string by the format specifiers in format.
locale
The locale to use.
Return Value
Both of these functions returns the number of fields successfully converted and assigned; the return value does not include fields that were read but not assigned. A return value of 0 indicates that no fields were assigned. The return value is EOF for an error or if the end of the string is reached before the first conversion. For more information, see sscanf.
If input or format is a NULL pointer, or if length is less than or equal to zero, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, these functions return EOF and set errno to EINVAL.
For information about these and other error codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.
Remarks
This function is like sscanf except that it provides the ability to specify a fixed number of characters to examine from the input string. For more information, see sscanf.
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 |
|---|---|---|---|
_sntscanf |
_snscanf |
_snscanf |
_snwscanf |
_sntscanf_l |
_snscanf_l |
_snscanf_l |
_snwscanf_l |
Requirements
| Routine | Required header |
|---|---|
_snscanf, _snscanf_l |
<stdio.h> |
_snwscanf, _snwscanf_l |
<stdio.h> or <wchar.h> |
For more compatibility information, see Compatibility in the Introduction.
Example
// crt_snscanf.c
// compile with: /W3
#include <stdio.h>
int main( )
{
char str1[] = "15 12 14...";
wchar_t str2[] = L"15 12 14...";
char s1[3];
wchar_t s2[3];
int i;
float fp;
i = _snscanf( str1, 6, "%s %f", s1, &fp); // C4996
// Note: _snscanf is deprecated; consider using _snscanf_s instead
printf("_snscanf converted %d fields: ", i);
printf("%s and %f\n", s1, fp);
i = _snwscanf( str2, 6, L"%s %f", s2, &fp); // C4996
// Note: _snwscanf is deprecated; consider using _snwscanf_s instead
wprintf(L"_snwscanf converted %d fields: ", i);
wprintf(L"%s and %f\n", s2, fp);
}
_snscanf converted 2 fields: 15 and 12.000000
_snwscanf converted 2 fields: 15 and 12.000000
.NET Framework Equivalent
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.