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	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. All advertising materials mentioning features or use of this software
	17	.\" must display the following acknowledgement:
	18	.\" This product includes software developed by the University of
	19	.\" California, Berkeley and its contributors.
	20	.\" 4. Neither the name of the University nor the names of its contributors
	21	.\" may be used to endorse or promote products derived from this software
	22	.\" without specific prior written permission.
	23	.\"
	24	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	25	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	26	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	27	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	28	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	29	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	30	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	31	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	32	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	33	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	34	.\" SUCH DAMAGE.
	35	.\"
	36	.\" @(#)fread.3 8.2 (Berkeley) 3/8/94
	37	.\" $FreeBSD: src/lib/libc/stdio/fread.3,v 1.9 2002/10/12 16:13:37 mike Exp $
	38	.\"
	39	.Dd March 8, 1994
	40	.Dt FREAD 3
	41	.Os
	42	.Sh NAME
	43	.Nm fread ,
	44	.Nm fwrite
	45	.Nd binary stream input/output
	46	.Sh LIBRARY
	47	.Lb libc
	48	.Sh SYNOPSIS
	49	.In stdio.h
	50	.Ft size_t
	51	.Fn fread "void * restrict ptr" "size_t size" "size_t nmemb" "FILE * restrict stream"
	52	.Ft size_t
	53	.Fn fwrite "const void * restrict ptr" "size_t size" "size_t nmemb" "FILE * restrict stream"
	54	.Sh DESCRIPTION
	55	The function
	56	.Fn fread
	57	reads
	58	.Fa nmemb
	59	objects, each
	60	.Fa size
	61	bytes long, from the stream pointed to by
	62	.Fa stream ,
	63	storing them at the location given by
	64	.Fa ptr .
	65	.Pp
	66	The function
	67	.Fn fwrite
	68	writes
	69	.Fa nmemb
	70	objects, each
	71	.Fa size
	72	bytes long, to the stream pointed to by
	73	.Fa stream ,
	74	obtaining them from the location given by
	75	.Fa ptr .
	76	.Sh RETURN VALUES
	77	The functions
	78	.Fn fread
	79	and
	80	.Fn fwrite
	81	advance the file position indicator for the stream
	82	by the number of bytes read or written.
	83	They return the number of objects read or written.
	84	If an error occurs, or the end-of-file is reached,
	85	the return value is a short object count (or zero).
	86	.Pp
	87	The function
	88	.Fn fread
	89	does not distinguish between end-of-file and error, and callers
	90	must use
	91	.Xr feof 3
	92	and
	93	.Xr ferror 3
	94	to determine which occurred.
	95	The function
	96	.Fn fwrite
	97	returns a value less than
	98	.Fa nmemb
	99	only if a write error has occurred.
	100	.Sh SEE ALSO
	101	.Xr read 2 ,
	102	.Xr write 2
	103	.Sh STANDARDS
	104	The functions
	105	.Fn fread
	106	and
	107	.Fn fwrite
	108	conform to
	109	.St -isoC .