xref: /freebsd/lib/libc/stdio/fputs.3 (revision 4b9d6057)
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32.Dd January 23, 2020
33.Dt FPUTS 3
34.Os
35.Sh NAME
36.Nm fputs ,
37.Nm fputs_unlocked ,
38.Nm puts
39.Nd output a line to a stream
40.Sh LIBRARY
41.Lb libc
42.Sh SYNOPSIS
43.In stdio.h
44.Ft int
45.Fn fputs "const char *str" "FILE *stream"
46.Ft int
47.Fn fputs_unlocked "const char *str" "FILE *stream"
48.Ft int
49.Fn puts "const char *str"
50.Sh DESCRIPTION
51The function
52.Fn fputs
53writes the string pointed to by
54.Fa str
55to the stream pointed to by
56.Fa stream .
57.\" The terminating
58.\" .Dv NUL
59.\" character is not written.
60.Pp
61The
62.Fn fputs_unlocked
63function is equivalent to
64.Fn fputs ,
65except that the caller is responsible for locking the stream with
66.Xr flockfile 3
67before calling it.
68This function may be used to avoid the overhead of locking the stream and to
69prevent races when multiple threads are operating on the same stream.
70.Pp
71The function
72.Fn puts
73writes the string
74.Fa str ,
75and a terminating newline character,
76to the stream
77.Dv stdout .
78.Sh RETURN VALUES
79The functions
80.Fn fputs
81and
82.Fn puts
83return a nonnegative integer on success and
84.Dv EOF
85on error.
86.Sh ERRORS
87.Bl -tag -width Er
88.It Bq Er EBADF
89The
90.Fa stream
91argument
92is not a writable stream.
93.El
94.Pp
95The functions
96.Fn fputs
97and
98.Fn puts
99may also fail and set
100.Va errno
101for any of the errors specified for the routines
102.Xr write 2 .
103.Sh SEE ALSO
104.Xr ferror 3 ,
105.Xr fputws 3 ,
106.Xr putc 3 ,
107.Xr stdio 3
108.Sh STANDARDS
109The functions
110.Fn fputs
111and
112.Fn puts
113conform to
114.St -isoC .
115