< cpp‎ | io‎ | c
C-style I/O
Types and objects
File access
Direct input/output
Unformatted input/output
Formatted input
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.


[edit] Parameters

str - character string to be written

[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.size(), stdin))
        const auto len = std::strlen(;
            "The input string:\n[%s] is %s and has the length %li characters.\n",
  , 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.");
        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.

[edit] See also

reads formatted input from stdin, a file stream or a buffer
(function) [edit]
gets a character string from a file stream
(function) [edit]
writes a character string to a file stream
(function) [edit]