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_cgets, _cgetws

Gets a character string from the console. More secure versions of these functions are available; see _cgets_s, _cgetws_s.

char *_cgets( 
   char *buffer 
);
wchar_t *_cgetws(
   wchar_t *buffer
);
template <size_t size>
char *_cgets( 
   char (&buffer)[size]
); // C++ only
template <size_t size>
wchar_t *_cgetws(
   wchar_t (&buffer)[size]
); // C++ only

Parameters

  • buffer
    Storage location for data.

Return Value

_cgets and _cgetws return a pointer to the start of the string, at buffer[2]. If buffer is NULL, these functions invoke the invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, they return NULL and set errno to EINVAL.

Remarks

These functions read a string of characters from the console and store the string and its length in the location pointed to by buffer. The buffer parameter must be a pointer to a character array. The first element of the array, buffer[0], must contain the maximum length (in characters) of the string to be read. The array must contain enough elements to hold the string, a terminating null character ('\0'), and 2 additional bytes. The function reads characters until a carriage return–line feed (CR-LF) combination or the specified number of characters is read. The string is stored starting at buffer[2]. If the function reads a CR-LF, it stores the null character ('\0'). The function then stores the actual length of the string in the second array element, buffer[1].

Because all editing keys are active when _cgets or_cgetws is called while in a console window, pressing the F3 key repeats the last entered entry.

In C++, these functions have template overloads that invoke the newer, secure counterparts of these functions. For more information, see Secure Template Overloads.

Generic-Text Routine Mappings

Tchar.h routine

_UNICODE and _MBCS not defined

_MBCS defined

_UNICODE defined

_cgetts

_cgets

_cgets

_cgetws

Requirements

Routine

Required header

_cgets

<conio.h>

_cgetws

<conio.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

Example

// crt_cgets.c
// compile with: /c /W3
// This program creates a buffer and initializes
// the first byte to the size of the buffer. Next, the
// program accepts an input string using _cgets and displays
// the size and text of that string.
 
#include <conio.h>
#include <stdio.h>
#include <errno.h>

int main( void )
{
   char buffer[83] = { 80 };  // Maximum characters in 1st byte
   char *result;

   printf( "Input line of text, followed by carriage return:\n");

   // Input a line of text:
   result = _cgets( buffer ); // C4996
   // Note: _cgets is deprecated; consider using _cgets_s
   if (!result)
   {
      printf( "An error occurred reading from the console:"
              " error code %d\n", errno);
   }
   else
   {   
      printf( "\nLine length = %d\nText = %s\n",
              buffer[1], result );
   }
}

A line of input.

Input line of text, followed by carriage return:
Line Length = 16
Text = A line of input.

See Also

Concepts

Console and Port I/O

_getch, _getwch