gets(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | BUGS | SEE ALSO | COLOPHON

GETS(3)                 Linux Programmer's Manual                GETS(3)

NAME         top

       gets - get a string from standard input (DEPRECATED)

SYNOPSIS         top

       #include <stdio.h>

       char *gets(char *s);

DESCRIPTION         top

       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         top

       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         top

       For an explanation of the terms used in this section, see
       attributes(7).

       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │Interface                             Attribute     Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │gets()                                │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO         top

       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         top

       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         top

       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         top

       This page is part of release 5.12 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/.

GNU                            2021-03-22                        GETS(3)

Pages that refer to this page: fgetc(3)stdio(3)feature_test_macros(7)