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 items of data, each size bytes long,
from the stream pointed to by stream, storing them at the location
given by ptr.
The function fwrite() writes nmemb items of data, each size bytes long,
to the stream pointed to by stream, obtaining them from the location
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.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├──────────────────┼───────────────┼─────────┤
│fread(), fwrite() │ Thread safety │ MT-Safe │
└──────────────────┴───────────────┴─────────┘
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, C89.
SEE ALSOread(2), write(2), feof(3), ferror(3), unlocked_stdio(3)COLOPHON
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latest version of this page, can be found at
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GNU 2015-07-23 FREAD(3)
