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_cgets_s, _cgetws_s

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Gets a character string from the console. These versions of _cgets and _cgetws have security enhancements, as described in Security features in the CRT.

Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported in Universal Windows Platform apps.

Syntax

errno_t _cgets_s(
   char *buffer,
   size_t numberOfElements,
   size_t *pSizeRead
);
errno_t _cgetws_s(
   wchar_t *buffer
   size_t numberOfElements,
   size_t *pSizeRead
);
template <size_t size>
errno_t _cgets_s(
   char (&buffer)[size],
   size_t *pSizeRead
); // C++ only
template <size_t size>
errno_t _cgetws_s(
   wchar_t (&buffer)[size],
   size_t *pSizeRead
); // C++ only

Parameters

buffer
Storage location for data.

numberOfElements
The size of the buffer in single-byte or wide characters, which is also the maximum number of characters to be read.

pSizeRead
The number of characters actually read.

Return value

The return value is zero if successful; otherwise, an error code if a failure occurs.

Error conditions

buffer numberOfElements pSizeRead Return Contents of buffer
NULL any any EINVAL n/a
not NULL zero any EINVAL not modified
not NULL any NULL EINVAL zero-length string

Remarks

_cgets_s and _cgetws_s read a string from the console and copy the string (with a null terminator) into buffer. _cgetws_s is the wide character version of the function; other than the character size, the behavior of these two functions is identical. The maximum size of the string to be read is passed in as the numberOfElements parameter. This size should include an extra character for the terminating null. The actual number of characters read is placed in pSizeRead.

If an error occurs during the operation or in the validating of the parameters, the invalid parameter handler is invoked, as described in Parameter validation. If execution is allowed to continue, errno is set to EINVAL, and EINVAL is returned.

In C++, the use of these functions is simplified by template overloads. The overloads can infer buffer length automatically, which eliminates the need to specify a size argument. They can also automatically replace older, less-secure functions with their newer, more secure counterparts. For more information, see Secure template overloads.

The debug library versions of these functions first fill the buffer with 0xFE. To disable this behavior, use _CrtSetDebugFillThreshold.

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

Generic-text routine mappings

Tchar.h routine _UNICODE and _MBCS not defined _MBCS defined _UNICODE defined
_cgetts_s _cgets_s _cgets_s _cgetws_s

Requirements

Routine Required header
_cgets_s <conio.h>
_cgetws_s <conio.h> or <wchar.h>

For more compatibility information, see Compatibility.

See also

Console and port I/O
_getch, _getwch