mirror of https://github.com/mkerrisk/man-pages
79 lines
2.8 KiB
Plaintext
79 lines
2.8 KiB
Plaintext
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
|
|
.TH "GETS" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
|
|
.\" gets
|
|
.SH NAME
|
|
gets \- get a string from a stdin stream
|
|
.SH SYNOPSIS
|
|
.LP
|
|
\fB#include <stdio.h>
|
|
.br
|
|
.sp
|
|
char *gets(char *\fP\fIs\fP\fB);
|
|
.br
|
|
\fP
|
|
.SH DESCRIPTION
|
|
.LP
|
|
The \fIgets\fP() function shall read bytes from the standard input
|
|
stream, \fIstdin\fP, into the array pointed to by \fIs\fP,
|
|
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.
|
|
.LP
|
|
The
|
|
\fIgets\fP() function may mark the \fIst_atime\fP field of the file
|
|
associated with \fIstream\fP for update. The \fIst_atime\fP
|
|
field shall be marked for update by the first successful execution
|
|
of \fIfgetc\fP(), \fIfgets\fP(), \fIfread\fP(), \fIgetc\fP(), \fIgetchar\fP(),
|
|
\fIgets\fP(), \fIfscanf\fP(), or \fIscanf\fP() using \fIstream\fP
|
|
that
|
|
returns data not supplied by a prior call to \fIungetc\fP().
|
|
.SH RETURN VALUE
|
|
.LP
|
|
Upon successful completion, \fIgets\fP() shall return \fIs\fP. If
|
|
the stream is at end-of-file, the end-of-file indicator for
|
|
the stream shall be set and \fIgets\fP() shall return a null pointer.
|
|
If a read error occurs, the error indicator for the stream
|
|
shall be set, \fIgets\fP() shall return a null pointer, \ and set
|
|
\fIerrno\fP to indicate the error.
|
|
.SH ERRORS
|
|
.LP
|
|
Refer to \fIfgetc\fP() .
|
|
.LP
|
|
\fIThe following sections are informative.\fP
|
|
.SH EXAMPLES
|
|
.LP
|
|
None.
|
|
.SH APPLICATION USAGE
|
|
.LP
|
|
Reading a line that overflows the array pointed to by \fIs\fP results
|
|
in undefined behavior. The use of \fIfgets\fP() is recommended.
|
|
.LP
|
|
Since the user cannot specify the length of the buffer passed to \fIgets\fP(),
|
|
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.
|
|
.LP
|
|
It is recommended that the \fIfgets\fP() function should be used to
|
|
read input lines.
|
|
.SH RATIONALE
|
|
.LP
|
|
None.
|
|
.SH FUTURE DIRECTIONS
|
|
.LP
|
|
None.
|
|
.SH SEE ALSO
|
|
.LP
|
|
\fIfeof\fP() , \fIferror\fP() , \fIfgets\fP() ,
|
|
the Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<stdio.h>\fP
|
|
.SH COPYRIGHT
|
|
Portions of this text are reprinted and reproduced in electronic form
|
|
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
|
|
-- Portable Operating System Interface (POSIX), The Open Group Base
|
|
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
|
|
Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
|