GETS
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Page Index
NAME
gets - get a string from standard input (DEPRECATED)
SYNOPSIS
#include <stdio.h>
char *gets(char *s);
DESCRIPTION
Never use this function.
gets()
reads a line from
stdin
into the buffer pointed to by
s
until either a terminating newline or
EOF,
which it replaces with a null byte ('\0').
No check for buffer overrun is performed (see BUGS below).
RETURN VALUE
gets()
returns
s
on success, and NULL
on error or when end of file occurs while no characters have been read.
However, given the lack of buffer overrun checking, there can be no
guarantees that the function will even return.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
| Interface | Attribute | Value
|
|
gets()
| Thread safety | MT-Safe
|
CONFORMING TO
C89, C99, POSIX.1-2001.
LSB deprecates
gets().
POSIX.1-2008 marks
gets()
obsolescent.
ISO C11 removes the specification of
gets()
from the C language, and since version 2.16,
glibc header files don't expose the function declaration if the
_ISOC11_SOURCE
feature test macro is defined.
BUGS
Never use
gets().
Because it is impossible to tell without knowing the data in advance how many
characters
gets()
will read, and because
gets()
will continue to store characters past the end of the buffer,
it is extremely dangerous to use.
It has been used to break computer security.
Use
fgets()
instead.
For more information, see CWE-242 (aka "Use of Inherently Dangerous
Function") at
http://cwe.mitre.org/data/definitions/242.html
SEE ALSO
read(2),
write(2),
ferror(3),
fgetc(3),
fgets(3),
fgetwc(3),
fgetws(3),
fopen(3),
fread(3),
fseek(3),
getline(3),
getwchar(3),
puts(3),
scanf(3),
ungetwc(3),
unlocked_stdio(3),
feature_test_macros(7)
COLOPHON
This page is part of release 5.10 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.