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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,  additionally
     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.  Therefore,
     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 altogether
     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 charac-
     ters.\n",
		  buf.data(), len + 1 < buf.size() ? "not  truncated"  :  "trun-
     cated", 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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