FREAD(S) XENIX System V FREAD(S)
Name
fread, fwrite - Performs buffered binary input and output.
Syntax
#include <stdio.h>
int fread (ptr, size, nitems, stream)
char *ptr;
int size, nitems;
FILE *stream;
int fwrite (ptr, size, nitems, stream)
char *ptr;
int size, nitems;
FILE *stream;
Description
fread reads, into a block beginning at ptr, nitems of data
of the type of *ptr from the named input stream, where an
item of data is a sequence of bytes (not necessarily
terminated by a null byte) of length size. fread stops
appending bytes if an end-of-file or error condition is
encountered while reading stream, or if nitems items have
been read. fread leaves the file pointer in stream, if
defined, pointing to the byte following the last byte read,
if there is one. fread does not change the contents of
stream. It returns the number of items actually read.
fwrite appends at most nitems of data of the type of *ptr
beginning at ptr to the named output stream. fwrite stops
appending when it has appended nitems items of data or if an
error condition is encountered on stream. fwrite does not
change the contents of the array pointed to by ptr. fwrite
increments the file pointer in stream, if defined, by the
number of bytes written. It returns the number of items
actually written.
See Also
fopen(S), getc(S), gets(S), printf(S), putc(S), puts(S),
read(S), scanf(S), write(S)
Diagnostics
fread and fwrite return the number of items read or written.
If sizeof or nitems is non-positive, no characters are read
or written and 0 is returned by both fread and fwrite.
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