1.\" $NetBSD: putc.3,v 1.7 2002/02/07 07:00:26 ross Exp $ 2.\" 3.\" Copyright (c) 1990, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Chris Torek and the American National Standards Committee X3, 8.\" on Information Processing Systems. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. All advertising materials mentioning features or use of this software 19.\" must display the following acknowledgement: 20.\" This product includes software developed by the University of 21.\" California, Berkeley and its contributors. 22.\" 4. Neither the name of the University nor the names of its contributors 23.\" may be used to endorse or promote products derived from this software 24.\" without specific prior written permission. 25.\" 26.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36.\" SUCH DAMAGE. 37.\" 38.\" @(#)putc.3 8.1 (Berkeley) 6/4/93 39.\" 40.Dd April 25, 2001 41.Dt PUTC 3 42.Os 43.Sh NAME 44.Nm fputc , 45.Nm putc , 46.Nm putchar , 47.Nm putc_unlocked , 48.Nm putchar_unlocked , 49.Nm putw 50.Nd output a character or word to a stream 51.Sh LIBRARY 52.Lb libc 53.Sh SYNOPSIS 54.Fd #include \*[Lt]stdio.h\*[Gt] 55.Ft int 56.Fn fputc "int c" "FILE *stream" 57.Ft int 58.Fn putc "int c" "FILE *stream" 59.Ft int 60.Fn putchar "int c" 61.Ft int 62.Fn putc_unlocked "int c" "FILE *stream" 63.Ft int 64.Fn putchar_unlocked "int c" 65.Ft int 66.Fn putw "int w" "FILE *stream" 67.Sh DESCRIPTION 68The 69.Fn fputc 70function 71writes the character 72.Fa c 73(converted to an ``unsigned char'') 74to the output stream pointed to by 75.Fa stream . 76.Pp 77.Fn putc 78acts essentially identically to 79.Fn fputc , 80but is a macro that expands in-line. It may evaluate 81.Fa stream 82more than once, so arguments given to 83.Fn putc 84should not be expressions with potential side effects. 85.Pp 86.Fn putchar 87is identical to 88.Fn putc 89with an output stream of 90.Em stdout . 91.Pp 92The 93.Fn putc_unlocked 94and 95.Fn putchar_unlocked 96functions provide functionality identical to that of 97.Fn putc 98and 99.Fn putchar , 100respectively, but do not perform implicit locking of the streams they 101operate on. 102In multi-threaded programs they may be used 103.Em only 104within a scope in which the stream 105has been successfully locked by the calling thread using either 106.Xr flockfile 3 107or 108.Xr ftrylockfile 3 , 109and may later be released using 110.Xr funlockfile 3 . 111.Pp 112The 113.Fn putw 114function 115writes the specified 116.Em int 117to the named output 118.Fa stream . 119.Sh RETURN VALUES 120The functions, 121.Fn fputc , 122.Fn putc 123and 124.Fn putchar 125return the character written. 126If an error occurs, the value 127.Dv EOF 128is returned. 129The 130.Fn putw 131function 132returns 0 on success; 133.Dv EOF 134is returned if 135a write error occurs, 136or if an attempt is made to write a read-only stream. 137.Sh SEE ALSO 138.Xr ferror 3 , 139.Xr fopen 3 , 140.Xr getc 3 , 141.Xr stdio 3 142.Sh STANDARDS 143The functions 144.Fn fputc , 145.Fn putc , 146and 147.Fn putchar , 148conform to 149.St -ansiC . 150The functions 151.Fn putc_unlocked 152and 153.Fn putchar_unlocked 154conform to 155.St -p1003.1-96 . 156A function 157.Fn putw 158function appeared in 159.At v6 . 160.Sh BUGS 161The size and byte order of an 162.Em int 163varies from one machine to another, and 164.Fn putw 165is not recommended for portable applications. 166