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.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
.TH "FGETS" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" fgets
.SH NAME
fgets \- get a string from a stream
.SH SYNOPSIS
.LP
\fB#include <stdio.h>
.br
.sp
char *fgets(char *restrict\fP \fIs\fP\fB, int\fP \fIn\fP\fB, FILE
*restrict\fP \fIstream\fP\fB);
.br
\fP
.SH DESCRIPTION
.LP
The \fIfgets\fP() function shall read bytes from \fIstream\fP into
the array pointed to by \fIs\fP, until \fIn\fP-1 bytes
are read, or a <newline> is read and transferred to \fIs\fP, or an
end-of-file condition is encountered. The string is then
terminated with a null byte.
.LP
The
\fIfgets\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(), \fIfgetwc\fP(), \fIfgetws\fP(),
\fIfread\fP(), \fIfscanf\fP(), \fIgetc\fP(), \fIgetchar\fP(), \fIgets\fP(),
or \fIscanf\fP() using \fIstream\fP that returns data not supplied
by a prior call to \fIungetc\fP() or \fIungetwc\fP().
.SH RETURN VALUE
.LP
Upon successful completion, \fIfgets\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 \fIfgets\fP() shall return a null pointer.
If a read error occurs, the error indicator for the stream
shall be set, \fIfgets\fP() shall return a null pointer, \ and shall
set \fIerrno\fP to indicate the error.
.SH ERRORS
.LP
Refer to \fIfgetc\fP() .
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.SS Reading Input
.LP
The following example uses \fIfgets\fP() to read each line of input.
{LINE_MAX}, which defines the maximum size of the input
line, is defined in the \fI<limits.h>\fP header.
.sp
.RS
.nf
\fB#include <stdio.h>
\&...
char line[LINE_MAX];
\&...
while (fgets(line, LINE_MAX, fp) != NULL) {
\&...
}
\&...
\fP
.fi
.RE
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIfopen\fP() , \fIfread\fP() , \fIgets\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 .
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