usr/src/lib/libc/stdio/putc.3

.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" Chris Torek.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)putc.3      6.4 (Berkeley) %G%
.\"
.TH PUTC 3 ""
.UC 7
.SH NAME
fputc, putc, putchar, putw \- put a character or word to a stream
.SH SYNOPSIS
.nf
.ft B
#include <stdio.h>

int
fputc(int c, FILE *stream);

int
putc(int c, FILE *stream);

int
putchar(int c);

int
putw(int w, FILE *stream);
.ft R
.fi
.SH DESCRIPTION
.I Fputc
writes the character
.I c
(converted to an ``unsigned char'')
to the specified output
.IR stream .
.PP
.I Putc
acts essentially identically to
.IR fputc ,
but is a macro that expands in-line.
.PP
.I Putchar
is identical to
.I putc
with an output stream of
.BR stdout .
.PP
.I Putw
writes the specified
.B int
to the named output
.IR stream .
.SH "RETURN VALUE"
These functions return the integer constant
.SM
.B EOF
upon write error,
or if an attempt is made to write a read-only stream.
.I Putw
returns 0 on success;
the other functions return the character printed.
.SH "SEE ALSO"
ferror(3), fopen(3), getc(3), stdio(3)
.SH BUGS
The size and byte order of an
.B int
varies from one machine to another, and
.I putw
is not recommended for portable applications.
.PP
Because it is implemented as a macro,
.I putc
treats a
.I stream
argument with side effects incorrectly.
In particular, ``putc(c, *f++);'' may not work sensibly
(although ``putc(*cp++, f);''
.I does
work correctly).