xref: /freebsd/lib/libc/stdio/fputs.3 (revision 19fae0f66023a97a9b464b3beeeabb2081f575b3)
1.\" Copyright (c) 1990, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" This code is derived from software contributed to Berkeley by
5.\" Chris Torek and the American National Standards Committee X3,
6.\" on Information Processing Systems.
7.\"
8.\" Redistribution and use in source and binary forms, with or without
9.\" modification, are permitted provided that the following conditions
10.\" are met:
11.\" 1. Redistributions of source code must retain the above copyright
12.\"    notice, this list of conditions and the following disclaimer.
13.\" 2. Redistributions in binary form must reproduce the above copyright
14.\"    notice, this list of conditions and the following disclaimer in the
15.\"    documentation and/or other materials provided with the distribution.
16.\" 3. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\"     @(#)fputs.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd January 23, 2020
36.Dt FPUTS 3
37.Os
38.Sh NAME
39.Nm fputs ,
40.Nm fputs_unlocked ,
41.Nm puts
42.Nd output a line to a stream
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In stdio.h
47.Ft int
48.Fn fputs "const char *str" "FILE *stream"
49.Ft int
50.Fn fputs_unlocked "const char *str" "FILE *stream"
51.Ft int
52.Fn puts "const char *str"
53.Sh DESCRIPTION
54The function
55.Fn fputs
56writes the string pointed to by
57.Fa str
58to the stream pointed to by
59.Fa stream .
60.\" The terminating
61.\" .Dv NUL
62.\" character is not written.
63.Pp
64The
65.Fn fputs_unlocked
66function is equivalent to
67.Fn fputs ,
68except that the caller is responsible for locking the stream with
69.Xr flockfile 3
70before calling it.
71This function may be used to avoid the overhead of locking the stream and to
72prevent races when multiple threads are operating on the same stream.
73.Pp
74The function
75.Fn puts
76writes the string
77.Fa str ,
78and a terminating newline character,
79to the stream
80.Dv stdout .
81.Sh RETURN VALUES
82The functions
83.Fn fputs
84and
85.Fn puts
86return a nonnegative integer on success and
87.Dv EOF
88on error.
89.Sh ERRORS
90.Bl -tag -width Er
91.It Bq Er EBADF
92The
93.Fa stream
94argument
95is not a writable stream.
96.El
97.Pp
98The functions
99.Fn fputs
100and
101.Fn puts
102may also fail and set
103.Va errno
104for any of the errors specified for the routines
105.Xr write 2 .
106.Sh SEE ALSO
107.Xr ferror 3 ,
108.Xr fputws 3 ,
109.Xr putc 3 ,
110.Xr stdio 3
111.Sh STANDARDS
112The functions
113.Fn fputs
114and
115.Fn puts
116conform to
117.St -isoC .
118