1.\" $NetBSD: putc.3,v 1.8 2002/10/01 17:24:06 wiz 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. 81It may evaluate 82.Fa stream 83more than once, so arguments given to 84.Fn putc 85should not be expressions with potential side effects. 86.Pp 87.Fn putchar 88is identical to 89.Fn putc 90with an output stream of 91.Em stdout . 92.Pp 93The 94.Fn putc_unlocked 95and 96.Fn putchar_unlocked 97functions provide functionality identical to that of 98.Fn putc 99and 100.Fn putchar , 101respectively, but do not perform implicit locking of the streams they 102operate on. 103In multi-threaded programs they may be used 104.Em only 105within a scope in which the stream 106has been successfully locked by the calling thread using either 107.Xr flockfile 3 108or 109.Xr ftrylockfile 3 , 110and may later be released using 111.Xr funlockfile 3 . 112.Pp 113The 114.Fn putw 115function 116writes the specified 117.Em int 118to the named output 119.Fa stream . 120.Sh RETURN VALUES 121The functions, 122.Fn fputc , 123.Fn putc 124and 125.Fn putchar 126return the character written. 127If an error occurs, the value 128.Dv EOF 129is returned. 130The 131.Fn putw 132function 133returns 0 on success; 134.Dv EOF 135is returned if 136a write error occurs, 137or if an attempt is made to write a read-only stream. 138.Sh SEE ALSO 139.Xr ferror 3 , 140.Xr fopen 3 , 141.Xr getc 3 , 142.Xr stdio 3 143.Sh STANDARDS 144The functions 145.Fn fputc , 146.Fn putc , 147and 148.Fn putchar , 149conform to 150.St -ansiC . 151The functions 152.Fn putc_unlocked 153and 154.Fn putchar_unlocked 155conform to 156.St -p1003.1-96 . 157A function 158.Fn putw 159function appeared in 160.At v6 . 161.Sh BUGS 162The size and byte order of an 163.Em int 164varies from one machine to another, and 165.Fn putw 166is not recommended for portable applications. 167