man3/puts.3

   1 '\" t
   2 .\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
   3 .\"
   4 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   5 .\"
   6 .\" Modified Sat Jul 24 18:42:59 1993 by Rik Faith (faith@cs.unc.edu)
   7 .TH puts 3 (date) "Linux man-pages (unreleased)"
   8 .SH NAME
   9 fputc, fputs, putc, putchar, puts \- output of characters and strings
  10 .SH LIBRARY
  11 Standard C library
  12 .RI ( libc ", " \-lc )
  13 .SH SYNOPSIS
  14 .nf
  15 .B #include <stdio.h>
  16 .PP
  17 .BI "int fputc(int " c ", FILE *" stream );
  18 .BI "int putc(int " c ", FILE *" stream );
  19 .BI "int putchar(int " c );
  20 .PP
  21 .BI "int fputs(const char *restrict " s ", FILE *restrict " stream );
  22 .BI "int puts(const char *" s );
  23 .fi
  24 .SH DESCRIPTION
  25 .BR fputc ()
  26 writes the character
  27 .IR c ,
  28 cast to an
  29 .IR "unsigned char" ,
  30 to
  31 .IR stream .
  32 .PP
  33 .BR putc ()
  34 is equivalent to
  35 .BR fputc ()
  36 except that it may be implemented as a macro which evaluates
  37 .I stream
  38 more than once.
  39 .PP
  40 .BI "putchar(" c )
  41 is equivalent to
  42 .BI "putc(" c ", " stdout ) \fR.
  43 .PP
  44 .BR fputs ()
  45 writes the string
  46 .I s
  47 to
  48 .IR stream ,
  49 without its terminating null byte (\[aq]\e0\[aq]).
  50 .PP
  51 .BR puts ()
  52 writes the string
  53 .I s
  54 and a trailing newline
  55 to
  56 .IR stdout .
  57 .PP
  58 Calls to the functions described here can be mixed with each other and with
  59 calls to other output functions from the
  60 .I stdio
  61 library for the same output stream.
  62 .PP
  63 For nonlocking counterparts, see
  64 .BR unlocked_stdio (3).
  65 .SH RETURN VALUE
  66 .BR fputc (),
  67 .BR putc (),
  68 and
  69 .BR putchar ()
  70 return the character written as an
  71 .I unsigned char
  72 cast to an
  73 .I int
  74 or
  75 .B EOF
  76 on error.
  77 .PP
  78 .BR puts ()
  79 and
  80 .BR fputs ()
  81 return a nonnegative number on success, or
  82 .B EOF
  83 on error.
  84 .SH ATTRIBUTES
  85 For an explanation of the terms used in this section, see
  86 .BR attributes (7).
  87 .ad l
  88 .nh
  89 .TS
  90 allbox;
  91 lbx lb lb
  92 l l l.
  93 Interface       Attribute       Value
  94 T{
  95 .BR fputc (),
  96 .BR fputs (),
  97 .BR putc (),
  98 .BR putchar (),
  99 .BR puts ()
 100 T}      Thread safety   MT-Safe
 101 .TE
 102 .hy
 103 .ad
 104 .sp 1
 105 .SH STANDARDS
 106 C11, POSIX.1-2008.
 107 .SH HISTORY
 108 POSIX.1-2001, C89, C99.
 109 .SH BUGS
 110 It is not advisable to mix calls to output functions from the
 111 .I stdio
 112 library with low-level calls to
 113 .BR write (2)
 114 for the file descriptor associated with the same output stream; the results
 115 will be undefined and very probably not what you want.
 116 .SH SEE ALSO
 117 .BR write (2),
 118 .BR ferror (3),
 119 .BR fgets (3),
 120 .BR fopen (3),
 121 .BR fputwc (3),
 122 .BR fputws (3),
 123 .BR fseek (3),
 124 .BR fwrite (3),
 125 .BR putwchar (3),
 126 .BR scanf (3),
 127 .BR unlocked_stdio (3)