PUTS(3P) POSIX Programmer's Manual PUTS(3P)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.
NAMEputs — put a string on standard output
SYNOPSIS
#include <stdio.h>
int puts(const char *s);
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.1‐2008
defers to the ISO C standard.
The puts() function shall write the string pointed to by s, followed by
a <newline>, to the standard output stream stdout. The terminating
null byte shall not be written.
The last data modification and last file status change timestamps of
the file shall be marked for update between the successful execution of
puts() and the next successful completion of a call to fflush() or
fclose() on the same stream or a call to exit() or abort().
RETURN VALUE
Upon successful completion, puts() shall return a non-negative number.
Otherwise, it shall return EOF, shall set an error indicator for the
stream, and errno shall be set to indicate the error.
ERRORS
Refer to fputc().
The following sections are informative.
EXAMPLES
Printing to Standard Output
The following example gets the current time, converts it to a string
using localtime() and asctime(), and prints it to standard output using
puts(). It then prints the number of minutes to an event for which it
is waiting.
#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.\n",
minutes_to_event);
...
APPLICATION USAGE
The puts() function appends a <newline>, while fputs() does not.
This volume of POSIX.1‐2008 requires that successful completion simply
return a non-negative integer. There are at least three known different
implementation conventions for this requirement:
* Return a constant value.
* Return the last character written.
* 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.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
Section 2.5, Standard I/O Streams, fopen(), fputs(), putc()
The Base Definitions volume of POSIX.1‐2008, <stdio.h>
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 Electri‐
cal 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.ker‐
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 PUTS(3P)
