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.TH PUTS "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"

.SH PROLOG

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.

.SH NAME

puts

\(em put a string on standard output

.SH SYNOPSIS

.LP

.nf

#include <stdio.h>

.P

int puts(const char *\fIs\fP);

.fi

.SH DESCRIPTION

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\(hy2008 defers to the ISO\ C standard.

.P

The

\fIputs\fR()

function shall write the string pointed to by

.IR s ,

followed by a

<newline>,

to the standard output stream

.IR stdout .

The terminating null byte shall not be written.

.P

The last data modification and last file status change timestamps

of the file shall be marked for update between the successful

execution of

\fIputs\fR()

and the next successful completion of a call to

\fIfflush\fR()

or

\fIfclose\fR()

on the same stream or a call to

\fIexit\fR()

or

\fIabort\fR().

.SH "RETURN VALUE"

Upon successful completion,

\fIputs\fR()

shall return a non-negative number. Otherwise, it shall return EOF,

shall set an error indicator for the stream,

and

.IR errno

shall be set to indicate the error.

.SH ERRORS

Refer to

.IR "\fIfputc\fR\^(\|)".

.LP

.IR "The following sections are informative."

.SH EXAMPLES

.SS "Printing to Standard Output"

.P

The following example gets the current time, converts it to a string

using

\fIlocaltime\fR()

and

\fIasctime\fR(),

and prints it to standard output using

\fIputs\fR().

It then prints the number of minutes to an event for which it is

waiting.

.sp

.RS 4

.nf

\fB

#include <time.h>

#include <stdio.h>

\&...

time_t now;

int minutes_to_event;

\&...

time(&now;;

printf("The time is ");

puts(asctime(localtime(&now)));

printf("There are %d minutes to the event.\en",

    minutes_to_event);

\&...

.fi \fR

.P

.RE

.SH "APPLICATION USAGE"

The

\fIputs\fR()

function appends a

<newline>,

while

\fIfputs\fR()

does not.

.P

This volume of POSIX.1\(hy2008 requires that successful completion simply return a non-negative

integer. There are at least three known different implementation

conventions for this requirement:

.IP " *" 4

Return a constant value.

.IP " *" 4

Return the last character written.

.IP " *" 4

Return the number of bytes written. Note that this implementation

convention cannot be adhered to for strings longer than

{INT_MAX}

bytes as the value would not be representable in the return type of the

function. For backwards compatibility, implementations can return the

number of bytes for strings of up to

{INT_MAX}

bytes, and return

{INT_MAX}

for all longer strings.

.SH RATIONALE

None.

.SH "FUTURE DIRECTIONS"

None.

.SH "SEE ALSO"

.IR "Section 2.5" ", " "Standard I/O Streams",

.IR "\fIfopen\fR\^(\|)",

.IR "\fIfputs\fR\^(\|)",

.IR "\fIputc\fR\^(\|)"

.P

The Base Definitions volume of POSIX.1\(hy2008,

.IR "\fB<stdio.h>\fP"

.SH COPYRIGHT

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 .