FREAD(3) Linux Programmer's Manual FREAD(3)NAME
fread, fwrite - binary stream input/output
SYNOPSIS
#include <stdio.h>
size_t fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
size_t fwrite(const void *ptr, size_t size, size_t nmemb,
FILE *stream);
DESCRIPTION
The function fread() reads nmemb elements of data, each size bytes
long, from the stream pointed to by stream, storing them at the loca‐
tion given by ptr.
The function fwrite() writes nmemb elements of data, each size bytes
long, to the stream pointed to by stream, obtaining them from the loca‐
tion given by ptr.
For nonlocking counterparts, see unlocked_stdio(3).
RETURN VALUE
On success, fread() and fwrite() return the number of items read or
written. This number equals the number of bytes transferred only when
size is 1. If an error occurs, or the end of the file is reached, the
return value is a short item count (or zero).
fread() does not distinguish between end-of-file and error, and callers
must use feof(3) and ferror(3) to determine which occurred.
CONFORMING TO
C89, POSIX.1-2001.
SEE ALSOread(2), write(2), feof(3), ferror(3), unlocked_stdio(3)COLOPHON
This page is part of release 3.65 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2012-03-30 FREAD(3)