std::gets
<cstdio>
(removed in C++14)
Reads stdin into given character string until a newline character is found or end-of-file occurs.
Contents
[edit] Parameters
[edit] 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 .
[edit] 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.
[edit] Example
#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.