xref: /freebsd/lib/libc/stdio/fputs.3 (revision 315ee00f)
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.\"
34.Dd January 23, 2020
35.Dt FPUTS 3
36.Os
37.Sh NAME
38.Nm fputs ,
39.Nm fputs_unlocked ,
40.Nm puts
41.Nd output a line to a stream
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In stdio.h
46.Ft int
47.Fn fputs "const char *str" "FILE *stream"
48.Ft int
49.Fn fputs_unlocked "const char *str" "FILE *stream"
50.Ft int
51.Fn puts "const char *str"
52.Sh DESCRIPTION
53The function
54.Fn fputs
55writes the string pointed to by
56.Fa str
57to the stream pointed to by
58.Fa stream .
59.\" The terminating
60.\" .Dv NUL
61.\" character is not written.
62.Pp
63The
64.Fn fputs_unlocked
65function is equivalent to
66.Fn fputs ,
67except that the caller is responsible for locking the stream with
68.Xr flockfile 3
69before calling it.
70This function may be used to avoid the overhead of locking the stream and to
71prevent races when multiple threads are operating on the same stream.
72.Pp
73The function
74.Fn puts
75writes the string
76.Fa str ,
77and a terminating newline character,
78to the stream
79.Dv stdout .
80.Sh RETURN VALUES
81The functions
82.Fn fputs
83and
84.Fn puts
85return a nonnegative integer on success and
86.Dv EOF
87on error.
88.Sh ERRORS
89.Bl -tag -width Er
90.It Bq Er EBADF
91The
92.Fa stream
93argument
94is not a writable stream.
95.El
96.Pp
97The functions
98.Fn fputs
99and
100.Fn puts
101may also fail and set
102.Va errno
103for any of the errors specified for the routines
104.Xr write 2 .
105.Sh SEE ALSO
106.Xr ferror 3 ,
107.Xr fputws 3 ,
108.Xr putc 3 ,
109.Xr stdio 3
110.Sh STANDARDS
111The functions
112.Fn fputs
113and
114.Fn puts
115conform to
116.St -isoC .
117