PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

GETS(3P)                  POSIX Programmer's Manual                 GETS(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       gets — get a string from a stdin stream

SYNOPSIS         top

       #include <stdio.h>

       char *gets(char *s);

DESCRIPTION         top

       The functionality described on this reference page is aligned with
       the ISO C standard. Any conflict between the requirements described
       here and the ISO C standard is unintentional. This volume of
       POSIX.1‐2008 defers to the ISO C standard.

       The gets() function shall read bytes from the standard input stream,
       stdin, into the array pointed to by s, until a <newline> is read or
       an end-of-file condition is encountered. Any <newline> shall be
       discarded and a null byte shall be placed immediately after the last
       byte read into the array.

       The gets() function may mark the last data access timestamp of the
       file associated with stream for update. The last data access
       timestamp shall be marked for update by the first successful
       execution of fgetc(), fgets(), fread(), fscanf(), getc(), getchar(),
       getdelim(), getline(), gets(), or scanf() using stream that returns
       data not supplied by a prior call to ungetc().

RETURN VALUE         top

       Upon successful completion, gets() shall return s.  If the end-of-
       file indicator for the stream is set, or if the stream is at end-of-
       file, the end-of-file indicator for the stream shall be set and
       gets() shall return a null pointer. If a read error occurs, the error
       indicator for the stream shall be set, gets() shall return a null
       pointer, and set errno to indicate the error.

ERRORS         top

       Refer to fgetc(3p).

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       Reading a line that overflows the array pointed to by s results in
       undefined behavior. The use of fgets() is recommended.

       Since the user cannot specify the length of the buffer passed to
       gets(), use of this function is discouraged. The length of the string
       read is unlimited. It is possible to overflow this buffer in such a
       way as to cause applications to fail, or possible system security
       violations.

       Applications should use the fgets() function instead of the
       obsolescent gets() function.

RATIONALE         top

       The standard developers decided to mark the gets() function as
       obsolescent even though it is in the ISO C standard due to the
       possibility of buffer overflow.

FUTURE DIRECTIONS         top

       The gets() function may be removed in a future version.

SEE ALSO         top

       Section 2.5, Standard I/O Streams, feof(3p), ferror(3p), fgets(3p)

       The Base Definitions volume of POSIX.1‐2008, stdio.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                            GETS(3P)