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std::gets(3)		      C++ Standard Libary		  std::gets(3)

NAME
       std::gets - std::gets

Synopsis
	  Defined in header <cstdio>
	  char*	gets( char* str	);    (deprecated in C++11)
				      (removed in C++14)

	  Reads	stdin into given character string until	a newline character is
       found or
	  end-of-file occurs.

Parameters
	  str -	character string to be written

Return value
	  str on success, a null pointer on failure.

	  If  the  failure has been caused by end of file condition, addition-
       ally sets the eof
	  indicator (see std::feof()) on stdin.	If the failure has been	caused
       by some other
	  error, sets the error	indicator (see std::ferror()) on stdin.

Notes
	  The std::gets() function does	not perform  bounds  checking.	There-
       fore, this function
	  is  extremely	 vulnerable  to	 buffer-overflow attacks. It cannot be
       used safely (unless
	  the program runs in an environment which restricts what  can	appear
       on stdin). For
	  this	reason,	the function was deprecated in C++11 and removed alto-
       gether in C++14.
	  std::fgets() may be used instead.

Example
       // Run this code

	#include <array>
	#include <cstdio>
	#include <cstring>

	int main()
	{
	    std::puts("Never use std::gets(). Use std::fgets() instead!");

	    std::array<char, 16> buf;

	    std::printf("Enter a string:\n>");

	    if (std::fgets(buf.data(), buf.size(), stdin))
	    {
		const auto len = std::strlen(buf.data());
		std::printf(
		    "The input string:\n[%s] is	%s  and	 has  the  length  %li
       characters.\n",
		    buf.data(),	 len  +	 1  <  buf.size()  ? "not truncated" :
       "truncated", len
		);
	    }
	    else if (std::feof(stdin))
	    {
		std::puts("Error: the end of stdin stream has been reached.");
	    }
	    else if (std::ferror(stdin))
	    {
		std::puts("I/O error when reading from stdin.");
	    }
	    else
	    {
		std::puts("Unknown stdin error.");
	    }
	}

Possible output:
	Never use std::gets(). Use std::fgets()	instead!
	Enter a	string:
	>Living	on Earth is expensive, but it does include a free trip	around
       the Sun.
	The input string:
	[Living	on Earth] is truncated and has the length 15 characters.

See also
	  scanf	 reads formatted input from stdin, a file stream or a buffer
	  fscanf (function)
	  sscanf
	  fgets	 gets a	character string from a	file stream
		 (function)
	  fputs	 writes	a character string to a	file stream
		 (function)
	  C documentation for
	  gets

http://cppreference.com		  2024.06.10			  std::gets(3)

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